CI: apkbuild-lint: add a skip-apkbuild-lint tag

As we are now moving to a newer, stricter version, we might want to skip
fixing APKBUILDs in some MRs. And this is in general useful to have.

Signed-off-by: Oliver Smith <ollieparanoid@postmarketos.org>
Part-of: <https://gitlab.postmarketos.org/postmarketOS/pmaports/-/merge_requests/8735>

.ci/lib/apkbuild_linting.py

@@ -38,6 +38,10 @@ def get_kconfigcheck_categories() -> list [str]:
 
 
 if __name__ == "__main__":
+    if common.commit_message_has_string("[ci:skip-apkbuild-lint]"):
+        print("WARNING: not linting deviceinfo files ([ci:skip-apkbuild-lint])")
+        exit(0)
+
     kconfigcheck_categories = get_kconfigcheck_categories()
     custom_valid_options += kconfigcheck_categories
     os.environ["CUSTOM_VALID_OPTIONS"] = " ".join(custom_valid_options)