Bump httplib2 from 0.18.0 to 0.19.0 in /resources (#19)

Bumps [httplib2](https://github.com/httplib2/httplib2) from 0.18.0 to 0.19.0.
- [Release notes](https://github.com/httplib2/httplib2/releases)
- [Changelog](https://github.com/httplib2/httplib2/blob/master/CHANGELOG)
- [Commits](httplib2/httplib2@v0.18.0...v0.19.0)

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

resources/requirements.txt

@@ -7,7 +7,7 @@ docutils==0.14
 Flask==1.0
 Flask-SQLAlchemy==2.2
 google-api-python-client==1.6.3
-httplib2==0.18.0
+httplib2==0.19.0
 idna==2.6
 itsdangerous==0.24
 Jinja2==2.9.6