Improve ray tests

[antonpirker]

… and show that actors are not supported

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Thank you for contributing to sentry-python! Please add tests to validate your changes, and lint your code using tox -e linters.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.89%. Comparing base (dfb84cc) to head (b9be174).
Report is 1 commits behind head on master.

✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3846   +/-   ##
=======================================
  Coverage   79.88%   79.89%           
=======================================
  Files         137      137           
  Lines       15385    15385           
  Branches     2611     2611           
=======================================
+ Hits        12291    12292    +1     
  Misses       2222     2222           
+ Partials      872      871    -1     

see 3 files with indirect coverage changes