Bump tox from 4.6.0 to 4.6.3 in /requirements (#1193)

Bumps [tox](https://github.com/tox-dev/tox) from 4.6.0 to 4.6.3.
- [Release notes](https://github.com/tox-dev/tox/releases)
- [Changelog](https://github.com/tox-dev/tox/blob/main/docs/changelog.rst)
- [Commits](tox-dev/tox@4.6.0...4.6.3)

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

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

Author: dependabot[bot]

requirements/tox.txt

@@ -1,3 +1,3 @@
 -r ./coverage.txt
-tox==4.6.0
+tox==4.6.3
 tox-gh-actions==3.1.1