Package versioning

[codeboten]

Currently each release of opentelemetry-python updates the version numbers for all the packages and release a new version. This is causing unnecessary churn for users, as new packages should really only be released when a change has been made.

I would like to propose that only packages that include changes be released when a release is done. This would require some changes to the maintainer release process and CI tooling. It would also mean that versioning, which has been in sync thus far, will start diverging.

Please vote on this discussion:

• to keep versioning in sync and continue to release every package every time🚀
• to only release packages that have changed 🎉