Add possibility to override rubocop config locally

.gitignore

@@ -134,8 +134,10 @@ structure.sql
 /.envrc
 /.direnv
 
-# lefthook.yml user override
+# local user override
 lefthook-local.yml
+.rubocop-local.yml
+
 frontend/package-lock.json
 
 # Testing and nextcloud infrastructure

.rubocop.yml

@@ -6,6 +6,11 @@ require:
   - rubocop-capybara
   - rubocop-factory_bot
 
+<% if File.exist?('.rubocop-local.yml') %>
+inherit_from:
+  - .rubocop-local.yml
+<% end %>
+
 inherit_mode:
   merge:
     # adding files to Exclude should merge with inherited instead of replacing