Fix failing tests due to extended exemplars

Micrometer introduced extended exemplars functionality that adds
exemplars to _count too not only to histogram buckets,
see: micrometer-metrics/micrometer#3996
Because of this, some verifications should be changed.

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/tracing/prometheus/PrometheusExemplarsAutoConfigurationTests.java

@@ -16,6 +16,10 @@
 
 package org.springframework.boot.actuate.autoconfigure.tracing.prometheus;
 
+import java.util.Optional;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 import io.micrometer.observation.Observation;
 import io.micrometer.observation.ObservationRegistry;
 import io.micrometer.prometheus.PrometheusMeterRegistry;
@@ -34,6 +38,7 @@
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 
+import static org.apache.commons.lang3.StringUtils.countMatches;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.Mockito.mock;
 
@@ -44,6 +49,12 @@
  */
 class PrometheusExemplarsAutoConfigurationTests {
 
+	private static final Pattern BUCKET_TRACE_INFO_PATTERN = Pattern.compile(
+			"^test_observation_seconds_bucket\\{error=\"none\",le=\".+\"} 1.0 # \\{span_id=\"(\\p{XDigit}+)\",trace_id=\"(\\p{XDigit}+)\"} .+$");
+
+	private static final Pattern COUNTER_TRACE_INFO_PATTERN = Pattern.compile(
+			"^test_observation_seconds_count\\{error=\"none\"} 1.0 # \\{span_id=\"(\\p{XDigit}+)\",trace_id=\"(\\p{XDigit}+)\"} .+$");
+
 	private final ApplicationContextRunner contextRunner = new ApplicationContextRunner()
 		.withPropertyValues("management.tracing.sampling.probability=1.0",
 				"management.metrics.distribution.percentiles-histogram.all=true")
@@ -80,9 +91,27 @@ void prometheusOpenMetricsOutputShouldContainExemplars() {
 			Observation.start("test.observation", observationRegistry).stop();
 			PrometheusMeterRegistry prometheusMeterRegistry = context.getBean(PrometheusMeterRegistry.class);
 			String openMetricsOutput = prometheusMeterRegistry.scrape(TextFormat.CONTENT_TYPE_OPENMETRICS_100);
-			assertThat(openMetricsOutput).contains("test_observation_seconds_bucket")
-				.containsOnlyOnce("trace_id=")
-				.containsOnlyOnce("span_id=");
+
+			assertThat(openMetricsOutput).contains("test_observation_seconds_bucket");
+			assertThat(openMetricsOutput).containsOnlyOnce("test_observation_seconds_count");
+			assertThat(countMatches(openMetricsOutput, "span_id")).isEqualTo(2);
+			assertThat(countMatches(openMetricsOutput, "trace_id")).isEqualTo(2);
+
+			Optional<TraceInfo> bucketTraceInfo = openMetricsOutput.lines()
+				.filter(line -> line.contains("test_observation_seconds_bucket") && line.contains("span_id"))
+				.map(BUCKET_TRACE_INFO_PATTERN::matcher)
+				.flatMap(Matcher::results)
+				.map(matchResult -> new TraceInfo(matchResult.group(2), matchResult.group(1)))
+				.findFirst();
+
+			Optional<TraceInfo> counterTraceInfo = openMetricsOutput.lines()
+				.filter(line -> line.contains("test_observation_seconds_count") && line.contains("span_id"))
+				.map(COUNTER_TRACE_INFO_PATTERN::matcher)
+				.flatMap(Matcher::results)
+				.map(matchResult -> new TraceInfo(matchResult.group(2), matchResult.group(1)))
+				.findFirst();
+
+			assertThat(bucketTraceInfo).isNotEmpty().contains(counterTraceInfo.orElse(null));
 		});
 	}
 
@@ -98,4 +127,7 @@ SpanContextSupplier customSpanContextSupplier() {
 
 	}
 
+	private record TraceInfo(String traceId, String spanId) {
+	}
+
 }