tox: remove lxml/xmlsec workaround

It now breaks things instead of fixing them - both modules now ship
wheels which are compatible.

Author: nijel

tox.ini

@@ -12,5 +12,4 @@ deps =
   py{38,39,310,311,312}: -rsocial_core/tests/requirements.txt
 commands =
   py{38,39,310,311,312}: pip install -e .[all]
-  py{38,39,310,311,312}: pip install --force-reinstall --no-binary lxml lxml
   pytest {posargs:-v --cov=social_core}