Bump pygments from 2.3.1 to 2.7.4

Bumps [pygments](https://github.com/pygments/pygments) from 2.3.1 to 2.7.4.
- [Release notes](https://github.com/pygments/pygments/releases)
- [Changelog](https://github.com/pygments/pygments/blob/master/CHANGES)
- [Commits](pygments/pygments@2.3.1...2.7.4)

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

requirements.txt

@@ -37,7 +37,7 @@ prompt-toolkit==2.0.9
 protobuf==3.6.1
 pycparser==2.19
 pyfakefs==3.5.7
-Pygments==2.3.1
+Pygments==2.7.4
 pyhcl==0.4.0
 pylint==2.2.2
 pyOpenSSL==19.0.0