Bump com.rabbitmq:amqp-client from 5.16.0 to 5.21.0 (#4917)

Bumps [com.rabbitmq:amqp-client](https://github.com/rabbitmq/rabbitmq-java-client) from 5.16.0 to 5.21.0.
- [Release notes](https://github.com/rabbitmq/rabbitmq-java-client/releases)
- [Commits](rabbitmq/rabbitmq-java-client@v5.16.0...v5.21.0)

---
updated-dependencies:
- dependency-name: com.rabbitmq:amqp-client
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

eventmesh-connectors/eventmesh-connector-rabbitmq/build.gradle

@@ -20,7 +20,7 @@ dependencies {
     api project(":eventmesh-openconnect:eventmesh-openconnect-java")
     implementation project(":eventmesh-common")
     // rabbitmq
-    implementation 'com.rabbitmq:amqp-client:5.16.0'
+    implementation 'com.rabbitmq:amqp-client:5.21.0'
 
     implementation 'io.cloudevents:cloudevents-json-jackson'
 

eventmesh-storage-plugin/eventmesh-storage-rabbitmq/build.gradle

@@ -19,12 +19,12 @@ dependencies {
     implementation project(":eventmesh-storage-plugin:eventmesh-storage-api")
     implementation project(":eventmesh-common")
     // rabbitmq
-    implementation 'com.rabbitmq:amqp-client:5.16.0'
+    implementation 'com.rabbitmq:amqp-client:5.21.0'
 
     testImplementation project(":eventmesh-storage-plugin:eventmesh-storage-api")
     testImplementation project(":eventmesh-common")
     // rabbitmq
-    testImplementation 'com.rabbitmq:amqp-client:5.16.0'
+    testImplementation 'com.rabbitmq:amqp-client:5.21.0'
 
     implementation 'io.cloudevents:cloudevents-json-jackson'
     testImplementation 'io.cloudevents:cloudevents-json-jackson'