remove git fetch from tox docs environment

Author: jakkdl

tox.ini

@@ -103,13 +103,7 @@ basepython = python3.12 # sync with rtd to get errors
 usedevelop = True
 deps =
     -r{toxinidir}/doc/en/requirements.txt
-allowlist_externals =
-  git
 commands =
-    # Retrieve possibly missing commits:
-    -git fetch --unshallow
-    -git fetch --tags
-
     sphinx-build \
       -j auto \
       -W --keep-going \