Adopt Rails 7.1's new BroadcastLogger

In rails/rails#48615, Rails 7.1 introduced a new
BroadcastLogger class that allows users to send logs to multiple loggers,
which means we need to adjust the SDK's logger assignment for it.

sentry-rails/.gitignore

@@ -5,7 +5,7 @@
 /doc/
 /pkg/
 /spec/reports/
-/spec/dummy/test_rails_app/db
+/spec/dummy/test_rails_app/db*
 /tmp/
 
 # rspec failure tracking

sentry-rails/lib/sentry/rails/configuration.rb

@@ -12,7 +12,12 @@ class Configuration
       @excluded_exceptions = @excluded_exceptions.concat(Sentry::Rails::IGNORE_DEFAULT)
 
       if ::Rails.logger
-        @logger = ::Rails.logger.dup
+        if ::Rails.logger.respond_to?(:broadcasts)
+          dupped_broadcasts = ::Rails.logger.broadcasts.map(&:dup)
+          @logger = ::ActiveSupport::BroadcastLogger.new(*dupped_broadcasts)
+        else
+          @logger = ::Rails.logger.dup
+        end
       else
         @logger.warn(Sentry::LOGGER_PROGNAME) do
           <<~MSG

sentry-rails/spec/sentry/rails_spec.rb

@@ -36,11 +36,23 @@
 
     describe "logger detection" do
       it "sets a duplicated Rails logger as the SDK's logger" do
-        expect(Sentry.configuration.logger).to be_a(ActiveSupport::Logger)
-        Sentry.configuration.logger.level = ::Logger::WARN
-        # Configuring the SDK's logger should not affect the Rails logger
-        expect(Rails.logger.level).to eq(::Logger::DEBUG)
-        expect(Sentry.configuration.logger.level).to eq(::Logger::WARN)
+        if Gem::Version.new(Rails.version) > Gem::Version.new("7.0.0")
+          expect(Sentry.configuration.logger).to be_a(ActiveSupport::BroadcastLogger)
+
+          Sentry.configuration.logger.level = ::Logger::WARN
+
+          # Configuring the SDK's logger should not affect the Rails logger
+          expect(Rails.logger.broadcasts.first.level).to eq(::Logger::DEBUG)
+          expect(Sentry.configuration.logger.level).to eq(::Logger::WARN)
+        else
+          expect(Sentry.configuration.logger).to be_a(ActiveSupport::Logger)
+
+          Sentry.configuration.logger.level = ::Logger::WARN
+
+          # Configuring the SDK's logger should not affect the Rails logger
+          expect(Rails.logger.level).to eq(::Logger::DEBUG)
+          expect(Sentry.configuration.logger.level).to eq(::Logger::WARN)
+        end
       end
 
       it "respects the logger set by user" do