Bump coverage[toml] from 7.3.0 to 7.3.1

Bumps [coverage[toml]](https://github.com/nedbat/coveragepy) from 7.3.0 to 7.3.1.
- [Release notes](https://github.com/nedbat/coveragepy/releases)
- [Changelog](https://github.com/nedbat/coveragepy/blob/master/CHANGES.rst)
- [Commits](nedbat/coveragepy@7.3.0...7.3.1)

---
updated-dependencies:
- dependency-name: coverage[toml]
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

setup.cfg

@@ -88,7 +88,7 @@ install_requires =
 # Extras used by developers *of* briefcase are pinned to specific versions to
 # ensure environment consistency.
 dev =
-    coverage[toml] == 7.3.0
+    coverage[toml] == 7.3.1
     coverage-conditional-plugin == 0.9.0
     pre-commit == 3.4.0
     pytest == 7.4.1