Emit warning if deprecated/removed options are used

Author: github-actions[bot]

entrypoint.sh

@@ -27,6 +27,18 @@ _log() {
 }
 
 _main() {
+    if "$INPUT_SKIP_FETCH"; then
+        _log "warning" "skip_fetch has been removed in v6. It does not have any effect anymore.";
+    fi
+
+    if "$INPUT_SKIP_CHECKOUT"; then
+        _log "warning" "skip_checkout has been removed in v6. It does not have any effect anymore.";
+    fi
+
+    if "$INPUT_CREATE_BRANCH"; then
+        _log "warning" "create_branch has been removed in v6. It does not have any effect anymore.";
+    fi
+
     _check_if_git_is_available
 
     _switch_to_repository