Update importlib-metadata requirement from <8.5 to <8.6

Updates the requirements on [importlib-metadata](https://github.com/python/importlib_metadata) to permit the latest version.
- [Release notes](https://github.com/python/importlib_metadata/releases)
- [Changelog](https://github.com/python/importlib_metadata/blob/main/NEWS.rst)
- [Commits](python/importlib_metadata@0.1...v8.5.0)

---
updated-dependencies:
- dependency-name: importlib-metadata
  dependency-type: direct:production
...

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

test_reqs.txt

@@ -1,6 +1,6 @@
 Markdown==3.7  # pyup: <3.2
 coverage==7.6.1
-importlib_metadata<8.5
+importlib_metadata<8.6
 typing_extensions==4.12.2
 zipp==3.20.1  # for flake8
 flake8==7.1.1