Bump pygments from 2.8.0 to 2.8.1

Bumps [pygments](https://github.com/pygments/pygments) from 2.8.0 to 2.8.1.
- [Release notes](https://github.com/pygments/pygments/releases)
- [Changelog](https://github.com/pygments/pygments/blob/2.8.1/CHANGES)
- [Commits](pygments/pygments@2.8.0...2.8.1)

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

Author: dependabot-preview[bot]

dev-requirements.txt

@@ -2,7 +2,7 @@
 # the setup function because Read The Docs needs a requirements file.
 black==20.8b1
 PyYAML==5.4.1
-Pygments==2.8.0
+Pygments==2.8.1
 Sphinx-Substitution-Extensions==2020.9.30.0
 Sphinx==3.5.1
 VWS-Python-Mock==2020.10.3.0