Merge pull request #1521 from matrix-org/dbkr/geni18n-addplural

Fix bug with gen-i18n/js when adding new plurals

scripts/gen-i18n.js

@@ -233,7 +233,7 @@ for (const path of SEARCH_PATHS) {
 const trObj = {};
 for (const tr of translatables) {
     trObj[tr] = tr;
-    if (tr.includes("|")) {
+    if (tr.includes("|") && inputTranslationsRaw[tr]) {
         trObj[tr] = inputTranslationsRaw[tr];
     }
 }