Bump lxml from 4.6.2 to 4.6.3

Bumps [lxml](https://github.com/lxml/lxml) from 4.6.2 to 4.6.3.
- [Release notes](https://github.com/lxml/lxml/releases)
- [Changelog](https://github.com/lxml/lxml/blob/master/CHANGES.txt)
- [Commits](lxml/lxml@lxml-4.6.2...lxml-4.6.3)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

requirements.txt

@@ -28,7 +28,7 @@ html2text==2020.1.16
 humanize==3.3.0
 jira==2.0.0
 PyGithub==1.54.1
-lxml==4.6.2
+lxml==4.6.3
 Markdown==3.3.4
 mysqlclient==2.0.3
 openpyxl==3.0.7