Include deprecation in artifact description for CloudWatch v1 registry

[shakuzen]

In preparation of removing with #1473, we should mention the deprecation in the description of the artifact. While all the public API is already marked deprecated, there's a chance users are not directly using the API despite having a dependency on the module and it being used by another library. I worry that users may stop upgrading to new versions if they are only checking the latest version of micrometer-registry-cloudwatch in Maven Central. Once we remove the module it will no longer be published. If the deprecation notice is included in the artifact description, at least there's a chance users will notice when checking the latest version of micrometer-registry-cloudwatch in Maven Central, e.g. https://search.maven.org/artifact/io.micrometer/micrometer-registry-cloudwatch/1.12.3/jar