Move from deprecated test-results-action to codecov-action #5158
Description
Steps to Reproduce
CI runs have this warning in the upload test results to codecov step (e.g. https://github.com/python-telegram-bot/python-telegram-bot/actions/runs/22810050159/job/66165208277?pr=5142):
Run codecov/test-results-action@0fa95f0e1eeaafde2c782583b36b28ad0d8c77d3
Warning: This action is being deprecated in favor of 'codecov-action'.
Please update CI accordingly to use 'codecov-action@v5' with
'report_type: test_results'.
The 'codecov-action' should and can be run at least once for
coverage and once for test results
Expected behaviour
We should migrate to that action.
Actual behaviour
A warning is raised
Operating System
Invariant
Version of Python, python-telegram-bot & dependencies
-Relevant log output
Additional Context
No response