Corrected test dependencies

Author: Bernardo-MG

tox.ini

@@ -47,7 +47,6 @@ changedir =
     docs/source
 deps =
     -r{toxinidir}/requirements.txt
-    sphinx
 commands =
     sphinx-build -b linkcheck ./ {envtmpdir}/html
     sphinx-build -nW -b html -d {envtmpdir}/doctrees ./ {envtmpdir}/html