⬆️ Bump pygments from 2.4.2 to 2.7.4

Bumps [pygments](https://github.com/pygments/pygments) from 2.4.2 to 2.7.4.
- [Release notes](https://github.com/pygments/pygments/releases)
- [Changelog](https://github.com/pygments/pygments/blob/master/CHANGES)
- [Commits](pygments/pygments@2.4.2...2.7.4)

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

requirements-dev.txt

@@ -46,7 +46,7 @@ pycodestyle==2.5.0
     #   flake8
 pyflakes==2.1.1
     # via flake8
-pygments==2.4.2
+pygments==2.7.4
     # via readme-renderer
 pylint==2.3.1
     # via -r requirements-dev.in