Add updated usage to commit to be pushed

clickusagelib/githook.py

@@ -8,7 +8,7 @@ set -e
 if grep -qz '^--follow-tags$' /proc/$PPID/cmdline; then
     poetry run clickusagemd run pyproject.toml
     if ! git diff --quiet USAGE.md; then
-        git commit -m "Updated USAGE.md" USAGE.md
+        git commit --amend USAGE.md
     fi
 fi