Configure SSH signing for commits in workflow

Add SSH commit signing configuration to workflow

Author: navaneethsnair1

.github/workflows/make_blog_draft_pr.yml

@@ -42,6 +42,15 @@ jobs:
         uses: actions/checkout@v3
         with:
           ref: prod
+
+      - name: Configure SSH commit signing
+        run: |
+          mkdir -p ~/.ssh
+          echo "${{ secrets.SSH_SIGNING_KEY }}" > ~/.ssh/signing_key
+          chmod 600 ~/.ssh/signing_key
+          git config --global gpg.format ssh
+          git config --global user.signingkey ~/.ssh/signing_key
+          git config --global commit.gpgsign true
         
       - name: Create new branch ${{ inputs.version }}-post
         if: false
@@ -64,7 +73,7 @@ jobs:
           git config user.name github-actions
           git config user.email github-actions@github.com
           git add -A
-          git commit -m ${{ inputs.version }} --author "${{ github.actor }} <${{ github.actor }}@users.noreply.github.com>"
+          git commit -S -m ${{ inputs.version }} --author "${{ github.actor }} <${{ github.actor }}@users.noreply.github.com>"
           git push origin prod:${{ inputs.version }}-post
           echo "pr-url=$(gh pr create --base draft --head ${{ inputs.version }}-post --title "${{ inputs.version }} draft" --assignee ${{ github.actor }} --body "After this PR is merged, preview at draft site:&nbsp;${{ steps.gen-url.outputs.draft-url }}")" >> $GITHUB_OUTPUT