Converting lint-all.sh to lint-all.py.

Converting `lint-all.sh` to `lint-all.py`.

ci/lint/06_script.sh

@@ -22,7 +22,7 @@ test/lint/git-subtree-check.sh src/univalue
 test/lint/git-subtree-check.sh src/leveldb
 test/lint/git-subtree-check.sh src/crc32c
 test/lint/check-doc.py
-test/lint/lint-all.sh
+test/lint/lint-all.py
 
 if [ "$CIRRUS_REPO_FULL_NAME" = "bitcoin/bitcoin" ] && [ "$CIRRUS_PR" = "" ] ; then
     # Sanity check only the last few commits to get notified of missing sigs,