ci: rename commits ci script to check-changed-versions

So it actually explains what it does. In the process, make the name of
the Python file it executes also consistent.

Signed-off-by: Pablo Correa Gómez <pabloyoyoista@postmarketos.org>
Part-of: <https://gitlab.postmarketos.org/postmarketOS/pmaports/-/merge_requests/7868>

.ci/check-changed-versions.sh

@@ -17,4 +17,4 @@ if [ "$(id -u)" = 0 ]; then
 	exec su "${TESTUSER:-pmos}" -c "sh -e $0"
 fi
 
-.ci/lib/check_changed_aports_versions.py
+.ci/lib/check_changed_versions.py