Merge pull request #57 from greedo/dependabot/pip/lxml-4.9.1

Bump lxml from 4.6.5 to 4.9.1

Author: greedo

requirements.txt

@@ -3,5 +3,5 @@ pep8==1.6.2
 marshmallow>=2.15.1
 beautifulsoup4==4.4.1
 ordereddict==1.1
-lxml==4.6.5
+lxml==4.9.1
 six==1.9.0