text: Title: Deprecate Python 3.7
  Body: We have already deprecated Python 3.6 (#4295) and plan to remove support for it in RF 7.0 (#4294). Python 3.7 will reach its end-of-life in [June 2023](https://peps.python.org/pep-0537/) and it's clear RF 7.0 won't be released before that. In this situation it makes sense to drop also Python 3.7 support in RF 7.0 and thus we need to deprecate it now.
  
  Similarly as with Python 3.6 deprecation, it doesn't make sense to emit deprecation warnings or make any other code changes. We only need to make sure info about supported versions in the README and in the UG is correct and mention this in RF 6.1 release notes.