Update github-repo-stats action to use 'main' branch

Author: sbryngelson

.github/workflows/repostats.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: run-ghrs
-        uses: jgehrcke/github-repo-stats@RELEASE
+        uses: jgehrcke/github-repo-stats@main
         with:
           # Define the stats repository (the repo to fetch
           # stats for and to generate the report for).