build(deps): bump pygments from 2.18.0 to 2.20.0 in /web/rules (#2979)

Bumps [pygments](https://github.com/pygments/pygments) from 2.18.0 to 2.20.0.
- [Release notes](https://github.com/pygments/pygments/releases)
- [Changelog](https://github.com/pygments/pygments/blob/master/CHANGES)
- [Commits](https://github.com/pygments/pygments/compare/2.18.0...2.20.0)

---
updated-dependencies:
- dependency-name: pygments
  dependency-version: 2.20.0
  dependency-type: direct:production
...

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

web/rules/requirements.txt

@@ -1,3 +1,3 @@
 pyyaml==6.0.2
-pygments==2.18.0
+pygments==2.20.0
 -e ../..  # capa