docs: fix templates override example lefthook-local.yml (#951)

* Changed example to specify override in lefthook-local.yml

Author: ejohnso49

docs/mdbook/configuration/templates.md

@@ -23,7 +23,7 @@ pre-commit:
 ```
 
 ```yml
-# lefthook.yml
+# lefthook-local.yml
 
 templates:
   dip: dip # Will run: `dip bundle exec rubocop file1 file2 file3 ...`