Convert incremental coverage scripts to use json coverage report

[pavoljuhas]

Description of the issue

The current coverage checking script check/pytest-and-incremental-coverage relies on the coverage annotate command which is deprecated per nedbat/coveragepy@59b07a1. The coverage tool has json command for producing JSON report, which should provide equivalent data as coverage annotate.

Proposal

• update scripts check/pytest-and-incremental-coverage and check/pytest-changed-files-and-incremental-coverage to use coverage json instead of coverage annotate
• prune any orphaned code for processing coverage annotate output, for example in dev_tools/check_incremental_coverage_annotations.py
• move settings from dev_tools/conf/.coveragerc to pyproject.toml so developers can run check/pytest without having to use the --cov-config=.../to/.coveragerc option.

Benefits

• CI scripts will be future-proofed for the removal of coverage annotate

Cirq version

1.3.0.dev at b28bfce

[tgag17]

Hi! Can I work on this issue?

[pavoljuhas]

Hi! Can I work on this issue?

Sorry about a late reply, yes, of course! Feel free to reach out if you have questions.

[davidmerwin]

Could I help as well? @pavoljuhas and @tgag17

[davidmerwin]

This is my first time trying to team collab on GitHub, i was not able to send any commits because of access. I spent some time trying to help. If you all want to review this to see if its getting on track, or offer and guidance for improvement i would appreciate it! Here is a rough draft:
@pavoljuhas @tgag17

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-- snipped by pavoljuhas -- code changes should be submitted by PR

[pavoljuhas]

Hi @davidmerwin - please see the CONTRIBUTING.md file for instructions how to create a pull request. In short, you need to create your own fork of the Cirq repository, add commits there, and then create a PR towards this repository. Thank you.

[davidmerwin]

Hi @davidmerwin - please see the CONTRIBUTING.md file for instructions how to create a pull request. In short, you need to create your own fork of the Cirq repository, add commits there, and then create a PR towards this repository. Thank you.

Roger solid copy @pavoljuhas @CirqBot @davidmerwin