gui: Add Irish (ga) translation template (#9646)

Based on user request from Weblate, user `@aindriu80`.

Looks promising based on the profile:
https://hosted.weblate.org/user/aindriu80/ Not sure whether almost
30.000 translations in about one month is realistic for a human though.

gui/default/assets/lang/lang-ga.json

@@ -0,0 +1,2 @@
+{
+}