Update coverage requirement from <7.6,>=5.3 to >=5.3,<7.7

Updates the requirements on [coverage](https://github.com/nedbat/coveragepy) to permit the latest version.
- [Release notes](https://github.com/nedbat/coveragepy/releases)
- [Changelog](https://github.com/nedbat/coveragepy/blob/master/CHANGES.rst)
- [Commits](nedbat/coveragepy@coverage-5.3...7.6.0)

---
updated-dependencies:
- dependency-name: coverage
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

pyproject.toml

@@ -46,7 +46,7 @@ doc = [
     "sphinxcontrib-mermaid>0.7,<0.10.0",
 ]
 tests = [
-    "coverage>=5.3,<7.6",  # Lets us track what code is being tested
+    "coverage>=5.3,<7.7",  # Lets us track what code is being tested
     "pre-commit>=2.9,<3.8",  # Allow us to run pre-commit hooks in testing
     "pytest>=6.2,<8.3",  # test framework
     "pytest-console-scripts>=1.1,<1.5",  # Allow automatic testing of scripts