Update upmerge workflow to ignore config and body-end changes (#1267)

* update upmerge

Signed-off-by: sk593 <shruthikumar@microsoft.com>

* readd signoff

Signed-off-by: sk593 <shruthikumar@microsoft.com>

---------

Signed-off-by: sk593 <shruthikumar@microsoft.com>

.github/workflows/upmerge.yaml

@@ -62,15 +62,15 @@ jobs:
           export SOURCE_BRANCH=$(basename ${{ github.ref }})
           echo "Upmerging docs from $SOURCE_BRANCH to edge"
           git fetch origin $SOURCE_BRANCH
-          
-          git merge -m "Upmerge to edge" origin/$SOURCE_BRANCH
+          git merge --no-commit origin/$SOURCE_BRANCH
+          git checkout edge -- docs/config.toml docs/layouts/partials/hooks/body-end.html
+          git commit -m "Upmerge to edge"
           
           if git diff --quiet edge; then
               echo "No changes to merge from $SOURCE_BRANCH to edge"
               echo "NO_CHANGES=true" >> $GITHUB_ENV
           else
               echo "Pushing $BRANCH_NAME for PR to edge"
-              git reset HEAD docs/config.toml docs/layouts/partials/hooks/body-end.html
               git push --set-upstream origin $BRANCH_NAME
           fi