Update virtualenv

scripts/common_startup.sh

@@ -142,9 +142,8 @@ if [ $SET_VENV -eq 1 ] && [ $CREATE_VENV -eq 1 ]; then
                 virtualenv -p "$GALAXY_PYTHON" "$GALAXY_VIRTUAL_ENV"
                 setup_gravity_state_dir
             else
-                vvers=16.7.9
-                vurl="https://files.pythonhosted.org/packages/source/v/virtualenv/virtualenv-${vvers}.tar.gz"
-                vsha=0d62c70883c0342d59c11d0ddac0d954d0431321a41ab20851facf2b222598f3
+                min_python_version=3.7
+                vurl="https://bootstrap.pypa.io/virtualenv/${min_python_version}/virtualenv.pyz"
                 vtmp=$(mktemp -d -t galaxy-virtualenv-XXXXXX)
                 vsrc="$vtmp/$(basename $vurl)"
                 # SSL certificates are not checked to prevent problems with messed
@@ -162,10 +161,7 @@ except:
     from urllib.request import urlretrieve
 urlretrieve('$vurl', '$vsrc')"
                 fi
-                echo "Verifying $vsrc checksum is $vsha"
-                "$GALAXY_PYTHON" -c "import hashlib; assert hashlib.sha256(open('$vsrc', 'rb').read()).hexdigest() == '$vsha', '$vsrc: invalid checksum'"
-                tar zxf "$vsrc" -C "$vtmp"
-                "$GALAXY_PYTHON" "$vtmp/virtualenv-$vvers/virtualenv.py" "$GALAXY_VIRTUAL_ENV"
+                "$GALAXY_PYTHON" "$vsrc" "$GALAXY_VIRTUAL_ENV"
                 rm -rf "$vtmp"
                 setup_gravity_state_dir
             fi