Bump coverage from 7.6.3 to 7.6.4 in /dev_requirements (#918)

Bumps [coverage](https://github.com/nedbat/coveragepy) from 7.6.3 to 7.6.4.
- [Release notes](https://github.com/nedbat/coveragepy/releases)
- [Changelog](https://github.com/nedbat/coveragepy/blob/master/CHANGES.rst)
- [Commits](coveragepy/coveragepy@7.6.3...7.6.4)

---
updated-dependencies:
- dependency-name: coverage
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

dev_requirements/requirements-coverage.txt

@@ -5,5 +5,5 @@
 #
 #    pip-compile-multi
 #
-coverage==7.6.3
+coverage==7.6.4
     # via -r requirements-coverage.in