stg-clean - Delete the empty patches in the series
stg clean
Delete the empty patches in the whole series or only those applied or unapplied. A patch is considered empty if the two commit objects representing its boundaries refer to the same tree object.
-a, --applied Delete the empty applied patches. -u, --unapplied Delete the empty unapplied patches.
Part of the StGit suite - see linkman:stg[1]