Merge pull request #492 from nexB/dependabot/pip/docs/pygments-2.7.4

Bump pygments from 2.6.1 to 2.7.4 in /docs

Author: pombredanne

docs/requirements.txt

@@ -9,7 +9,7 @@ imagesize==1.2.0
 Jinja2==2.11.3
 MarkupSafe==1.1.1
 packaging==20.3
-Pygments==2.6.1
+Pygments==2.7.4
 pyparsing==2.4.6
 pytz==2019.3
 requests==2.23.0