Bump lxml from 4.4.2 to 4.5.0 (#195)

Bumps [lxml](https://github.com/lxml/lxml) from 4.4.2 to 4.5.0.
- [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-4.4.2...lxml-4.5.0

)

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

requirements.txt

@@ -4,7 +4,7 @@ gevent==1.4.0
 gunicorn==20.0.4
 futures
 fuzzywuzzy==0.18.0
-lxml==4.4.2
+lxml==4.5.0
 matplotlib==2.2.5
 numpy==1.18.1
 nltk==3.4.5