Merge pull request #13146 from nextcloud/feat/document-oc-util-script-removal

feat: Document removal of OC_Util::addScript and friends

Author: susnux

developer_manual/app_publishing_maintenance/app_upgrade_guide/upgrade_to_32.rst

@@ -76,3 +76,11 @@ Removed APIs
   - ``maxUploadFilesize`` was deprecated since version 5.0.0 and replaced with ``\OCP\Util::maxUploadFilesize``
   - ``freeSpace`` was deprecated since version 7.0.0 and replaced with ``\OCP\Util::freeSpace``
   - ``uploadLimit`` was deprecated since version 7.0.0 and replaced with ``\OCP\Util::uploadLimit``
+
+- Removed deprecated methods of legacy ``\OC_Util`` class:
+
+  - ``addScript`` was replaced by ``\OCP\Util::addScript`` in 24
+  - ``addVendorScript`` was unused and removed
+  - ``addTranslations`` was replace by ``\OCP\Util::addTranslations`` in 24
+
+- Template function ``vendor_script`` was unused and removed