refactor(i18n): use common messages for generic button labels (#7020)

A few components defined their own "Cancel", "Close", "Clear" and
"Success" descriptors when commonMessages already has them. Swapped
them over and removed the old ones.

Locale files come from intl:prune-local dropping the now-orphaned
strings across every language.

packages/ui/src/locales/pt-PT/index.json

@@ -497,9 +497,6 @@
   "files.editor.file-saved-title": {
     "defaultMessage": "Ficheiro salvo"
   },
-  "files.editor.find-close": {
-    "defaultMessage": "Fechar"
-  },
   "files.editor.find-in-file": {
     "defaultMessage": "Encontrar"
   },
@@ -2526,4 +2523,3 @@
     "defaultMessage": "Tens alterações por guardar."
   }
 }
-