Revert building venv manually

Closes: #123

Author: zhsj

.github/scripts/build.sh

@@ -13,11 +13,5 @@ error() {
 cd cpython/Doc || exit 1
 mkdir -p locales/"$LOCALE"/
 ln -sfn "$(realpath ../../docs)" locales/"$LOCALE"/LC_MESSAGES
-
-# make venv
-# create venv manually, so we can specify sphinx version
-VENVDIR=./venv
-python3 -m venv $VENVDIR
-$VENVDIR/bin/python3 -m pip install -U pip setuptools
-$VENVDIR/bin/python3 -m pip install -r https://raw.githubusercontent.com/python/docsbuild-scripts/master/requirements.txt
-make html VENVDIR=$VENVDIR SPHINXOPTS="-D language=$LOCALE -D gettext_compact=0 -W --keep-going -j2" 2> >(error)
+make venv
+make html SPHINXOPTS="-D language=$LOCALE -D gettext_compact=0 -W --keep-going -j2" 2> >(error)