Merge pull request #16 from mozilla-services/dependabot/pip/pip-21.1

Bump pip from 19.2.3 to 21.1

Author: leplatrem

requirements_dev.txt

@@ -2,10 +2,10 @@ aioresponses==0.6.1
 Click==7.0
 coverage==4.5.4
 flake8==3.7.8
-pip==19.2.3
-pytest==4.6.5
+pip==21.1
+pytest==6.2.5
 pytest-aiohttp==0.3.0
-pytest-runner==5.1
+pytest-runner==5.3.1
 Sphinx==1.8.5
 tox==3.14.0
 twine==1.14.0