Bump elastic-apm to latest version (#330)

* chore: Install new elastic-apm pip dependency version

Made with ❤️️ by updatecli

* chore: Set org.label-schema.version in Dockerfile

Made with ❤️️ by updatecli

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Co-authored-by: apmmachine <apmmachine@users.noreply.github.com>

Dockerfile

@@ -41,7 +41,7 @@ LABEL \
     org.label-schema.schema-version="1.0" \
     org.label-schema.vendor="Elastic" \
     org.label-schema.name="opbeans-python" \
-    org.label-schema.version="6.20.0" \
+    org.label-schema.version="6.21.3" \
     org.label-schema.url="https://hub.docker.com/r/opbeans/opbeans-python" \
     org.label-schema.vcs-url="https://github.com/elastic/opbeans-python" \
     org.label-schema.license="MIT"