Add le-git-graph (#4397)

* Add le-git-graph

* Update index.md

Author: kevindevil2233

collections/github-browser-extensions/index.md

@@ -40,6 +40,7 @@ items:
  - npmhub/npmhub
  - octobox/extension
  - hypertrons/hypertrons-crx
+ - NirmalScaria/le-git-graph
 display_name: GitHub Browser Extensions
 created_by: leereilly
 ---