Update httplib2 requirement from <0.13.2 to <0.14.1

Updates the requirements on [httplib2](https://github.com/httplib2/httplib2) to permit the latest version.
- [Release notes](https://github.com/httplib2/httplib2/releases)
- [Changelog](https://github.com/httplib2/httplib2/blob/master/CHANGELOG)
- [Commits](httplib2/httplib2@0.9...v0.14.0)

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

requirements.txt

@@ -9,7 +9,7 @@ Django==1.11.24
 amqp==2.5.1
 pyyaml>=4.2b1
 beautifulsoup4==4.8.0
-httplib2<0.13.2
+httplib2<0.14.1
 hyperlink==19.0.0
 idna>=2.5,<2.9
 urllib3==1.25.6