Bump lxml from 4.5.2 to 4.6.2

Bumps [lxml](https://github.com/lxml/lxml) from 4.5.2 to 4.6.2.
- [Release notes](https://github.com/lxml/lxml/releases)
- [Changelog](https://github.com/lxml/lxml/blob/master/CHANGES.txt)
- [Commits](https://github.com/lxml/lxml/compare/lxml-4.5.2...lxml-4.6.2)

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

requirements.lock.txt

@@ -38,7 +38,7 @@ importlib-metadata==1.7.0
 itsdangerous==1.1.0
 Jinja2==2.11.2
 kombu==4.6.11
-lxml==4.5.2
+lxml==4.6.2
 Mako==1.1.3
 Markdown==3.2.2
 MarkupSafe==1.1.1

requirements.txt

@@ -21,7 +21,7 @@ celery ~= 4.4
 kombu ~= 4.6
 GitPython ~= 3.0
 git-archive-all ~= 1.21
-lxml ~= 4.2
+lxml ~= 4.6
 pillow ~= 7.0
 pyScss ~= 1.3
 redis ~= 3.3