Release updates for Cloudfoundry Repo (#15072)

Co-authored-by: otelbot <[email protected]>

Author: otelbot[bot]

index.yml

@@ -98,3 +98,4 @@
 2.19.0: https://repo1.maven.org/maven2/io/opentelemetry/javaagent/opentelemetry-javaagent/2.19.0/opentelemetry-javaagent-2.19.0.jar
 2.20.0: https://repo1.maven.org/maven2/io/opentelemetry/javaagent/opentelemetry-javaagent/2.20.0/opentelemetry-javaagent-2.20.0.jar
 2.20.1: https://repo1.maven.org/maven2/io/opentelemetry/javaagent/opentelemetry-javaagent/2.20.1/opentelemetry-javaagent-2.20.1.jar
+2.21.0: https://repo1.maven.org/maven2/io/opentelemetry/javaagent/opentelemetry-javaagent/2.21.0/opentelemetry-javaagent-2.21.0.jar