Removed unnecessary test dependencies when building docs (#1116)

Removed unnecessary test dependencies when building docs

Author: sliverc

tox.ini

@@ -42,7 +42,6 @@ commands = flake8
 [testenv:docs]
 basepython = python3.8
 deps =
-    -rrequirements/requirements-testing.txt
     -rrequirements/requirements-optionals.txt
     -rrequirements/requirements-documentation.txt
 commands =