build(deps): bump pygments from 2.4.0 to 2.18.0

Bumps [pygments](https://github.com/pygments/pygments) from 2.4.0 to 2.18.0.
- [Release notes](https://github.com/pygments/pygments/releases)
- [Changelog](https://github.com/pygments/pygments/blob/master/CHANGES)
- [Commits](pygments/pygments@2.4.0...2.18.0)

---
updated-dependencies:
- dependency-name: pygments
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

constraints-oldest.txt

@@ -11,7 +11,7 @@ flake8-bugbear==22.1.11
 flake8-comprehensions==3.7.0
 flynt==0.76
 mypy==0.990
-Pygments==2.4.0
+Pygments==2.18.0
 pytest==6.2.0
 pytest-kwparametrize==0.0.3
 regex==2021.4.4