Merge pull request #477 from searxng/dependabot/pip/master/lxml-4.6.4

Bump lxml from 4.6.3 to 4.6.4

requirements.txt

@@ -3,7 +3,7 @@ babel==2.9.1
 flask-babel==2.0.0
 flask==2.0.2
 jinja2==3.0.2
-lxml==4.6.3
+lxml==4.6.4
 pygments==2.10.0
 python-dateutil==2.8.2
 pyyaml==6.0