Replace full urls to xref wherever it is possible

Closes gh-4714

docs/modules/ROOT/pages/observation/projects.adoc

@@ -32,7 +32,7 @@ Micrometer Observation is used to instrument various projects. Below you can fin
 | RabbitMQ Stream | https://github.com/rabbitmq/rabbitmq-stream-java-client/pull/384[PR]
 | Resilience4j | https://github.com/resilience4j/resilience4j/pull/1698[PR]
 | R2DBC | https://github.com/r2dbc/r2dbc-proxy/issues/122[Issue]
-| Reactor | https://docs.micrometer.io/micrometer/reference/observation/instrumenting.html#instrumentation_of_reactive_libraries[Docs]
+| Reactor | xref:observation/instrumenting.adoc#instrumentation_of_reactive_libraries[Docs]
 | Reactor Netty | https://projectreactor.io/docs/netty/release/reference/index.html#_tracing_3[Docs]
 | Redisson | https://github.com/redisson/redisson/issues/4976[Issue],
 https://github.com/redisson/redisson/wiki/16.-Observability#162-tracing[Docs]

docs/modules/ROOT/pages/reference/db.adoc

@@ -11,7 +11,7 @@ Micrometer can instrument various libraries that interact with databases
 [[db-datasource-observation]]
 == DataSource Observation Instrumentation
 
-Through the https://github.com/jdbc-observations/datasource-micrometer[Datasource Micrometer] project you can instrument your `Datasource` to start producing https://docs.micrometer.io/micrometer/reference/observation.html[Observations] while interacting with the database. That means that depending on your Observation Handler setup you can plug in producing of metrics or distributed tracing.
+Through the https://github.com/jdbc-observations/datasource-micrometer[Datasource Micrometer] project you can instrument your `Datasource` to start producing xref:observation.adoc[Observations] while interacting with the database. That means that depending on your Observation Handler setup you can plug in producing of metrics or distributed tracing.
 
 You can read more about Datasource Micrometer https://jdbc-observations.github.io/datasource-micrometer/docs/current/docs/html/[reference documentation] here.
 

docs/modules/ROOT/pages/reference/grpc.adoc

@@ -3,7 +3,7 @@
 
 https://grpc.io/[gRPC] is a modern open source high performance Remote Procedure Call (RPC) framework that can run in any environment.
 
-Below you can find an example of how to instrument gRPC with https://docs.micrometer.io/micrometer/reference/observation.html[Micrometer Observation]. That means that depending on your Observation Handler configuration you instrument once, and can have multiple benefits out of it (e.g. metrics, distributed tracing).
+Below you can find an example of how to instrument gRPC with xref:observation.adoc[Micrometer Observation]. That means that depending on your Observation Handler configuration you instrument once, and can have multiple benefits out of it (e.g. metrics, distributed tracing).
 
 First, client and server side interceptors need to be setup.
 

docs/modules/ROOT/pages/reference/httpcomponents.adoc

@@ -5,7 +5,7 @@ IMPORTANT: This section requires usage of Apache HttpComponents Client at least
 
 https://hc.apache.org/index.html/[Apache HttpComponents Client] is an HTTP/1.1 compliant HTTP agent implementation.
 
-Below you can find an example of how to instrument Apache HttpComponents Client  with https://docs.micrometer.io/micrometer/reference/observation.html[Micrometer Observation]. That means that depending on your Observation Handler configuration you instrument once, and can have multiple benefits out of it (e.g. metrics, distributed tracing).
+Below you can find an example of how to instrument Apache HttpComponents Client xref:observation.adoc[Micrometer Observation]. That means that depending on your Observation Handler configuration you instrument once, and can have multiple benefits out of it (e.g. metrics, distributed tracing).
 
 Example of classic, blocking HTTP client.
 

docs/modules/ROOT/pages/reference/jetty.adoc

@@ -31,7 +31,7 @@ ServletContainer servletContainer = new ServletContainer(resourceConfig);
 [[overview-observation]]
 == Eclipse Observation Jersey Instrumentation
 
-Below you can find an example of how to instrument Jersey with https://docs.micrometer.io/micrometer/reference/observation.html[Micrometer Observation]. That means that depending on your Observation Handler configuration you instrument once, and can have multiple benefits out of it (e.g. metrics, distributed tracing).
+Below you can find an example of how to instrument Jersey with xref:observation.adoc[Micrometer Observation]. That means that depending on your Observation Handler configuration you instrument once, and can have multiple benefits out of it (e.g. metrics, distributed tracing).
 
 [source,java,subs=+attributes]
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docs/modules/ROOT/pages/reference/mongodb.adoc

@@ -5,7 +5,7 @@ https://www.mongodb.com/[MongoDB] is a modern database that supports transaction
 
 Below you can find an example of how to instrument MongoDb with Micrometer.
 
-TIP: To add more capabilities such as distributed tracing, please consider using https://docs.spring.io/spring-data/mongodb/reference/observability/observability.html[Spring Data MongoDb] which uses https://docs.micrometer.io/micrometer/reference/observation.html[Micrometer Observation] under the hood.
+TIP: To add more capabilities such as distributed tracing, please consider using https://docs.spring.io/spring-data/mongodb/reference/observability/observability.html[Spring Data MongoDb] which uses xref:observation.adoc[Micrometer Observation] under the hood.
 
 Below you can find an example of metrics for command execution.
 

docs/modules/ROOT/pages/reference/okhttpclient.adoc

@@ -6,7 +6,7 @@ Micrometer supports https://square.github.io/okhttp/[OkHttp Client] instrumentat
 [[okhttpclient-observation]]
 == OkHttpClient Observation
 
-Below you can find an example of how to instrument OkHttp Client  with https://docs.micrometer.io/micrometer/reference/observation.html[Micrometer Observation]. That means that depending on your Observation Handler configuration you instrument once, and can have multiple benefits out of it (e.g. metrics, distributed tracing).
+Below you can find an example of how to instrument OkHttp Client with xref:observation.adoc[Micrometer Observation]. That means that depending on your Observation Handler configuration you instrument once, and can have multiple benefits out of it (e.g. metrics, distributed tracing).
 
 [source,java,subs=+attributes]
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