Deprecate queue size property for StatsD metrics export

Closes gh-13108

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/metrics/export/statsd/StatsdProperties.java

@@ -21,6 +21,7 @@ import java.time.Duration;
 import io.micrometer.statsd.StatsdFlavor;
 
 import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.boot.context.properties.DeprecatedConfigurationProperty;
 
 /**
  * {@link ConfigurationProperties} for configuring StatsD metrics export.
@@ -122,10 +123,13 @@ public class StatsdProperties {
 		this.pollingFrequency = pollingFrequency;
 	}
 
+	@Deprecated
+	@DeprecatedConfigurationProperty(reason = "No longer configurable and an unbounded queue will always be used")
 	public Integer getQueueSize() {
 		return this.queueSize;
 	}
 
+	@Deprecated
 	public void setQueueSize(Integer queueSize) {
 		this.queueSize = queueSize;
 	}

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/metrics/export/statsd/StatsdPropertiesConfigAdapter.java

@@ -74,6 +74,7 @@ public class StatsdPropertiesConfigAdapter
 	}
 
 	@Override
+	@Deprecated
 	public int queueSize() {
 		return get(StatsdProperties::getQueueSize, StatsdConfig.super::queueSize);
 	}

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -280,7 +280,10 @@
     },
     {
       "name": "management.metrics.export.statsd.queue-size",
-      "defaultValue": 2147483647
+      "defaultValue": 2147483647,
+      "deprecation": {
+        "level": "error"
+      }
     },
     {
       "name": "management.trace.http.enabled",

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/metrics/export/statsd/StatsdPropertiesTests.java

@@ -38,7 +38,6 @@ public class StatsdPropertiesTests {
 		assertThat(properties.getPort()).isEqualTo(config.port());
 		assertThat(properties.getMaxPacketLength()).isEqualTo(config.maxPacketLength());
 		assertThat(properties.getPollingFrequency()).isEqualTo(config.pollingFrequency());
-		assertThat(properties.getQueueSize()).isEqualTo(config.queueSize());
 		assertThat(properties.isPublishUnchangedMeters())
 				.isEqualTo(config.publishUnchangedMeters());
 	}