Update coverage requirement from <7.3,>=5.3 to >=5.3,<7.4

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...7.3.0)

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

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

setup.py

@@ -37,7 +37,7 @@ def read(*parts):
 
 tests_require = [
     'codecov==2.1.*',
-    'coverage>=5.3,<7.3',
+    'coverage>=5.3,<7.4',
     'pytest-cov>=2.10,<4.2',
     'pytest-env>=0.6,<0.9',
     'pytest>=6.1,<7.5',