Don't specify repo/branch to check out

Don't specify which repo/branch to check out.  Action will do the right thing.

Co-authored-by: Naser Mahfouz <[email protected]>

.github/workflows/e3sm-gh-pages.yml

@@ -19,8 +19,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          repository: e3sm-project/e3sm
-          ref: master
+          show-progress: false
           fetch-depth: 0 # Needed, or else gh-pages won't be fetched, and push rejected
           submodules: false # speeds up clone and not building anything in submodules
       - name: Show action trigger