ci: use git pull --rebase in helm-pages.yml to avoid push conflicts

.github/workflows/helm-pages.yml

@@ -56,7 +56,8 @@ jobs:
             git config user.email "$GITHUB_ACTOR@users.noreply.github.com"
             git add README.md
             git commit -m "Auto-update Helm chart documentation"
-            git push
+            git pull --rebase origin main
+            git push origin main
           fi
           cd ../../..
 
@@ -100,7 +101,8 @@ jobs:
             git config user.email "$GITHUB_ACTOR@users.noreply.github.com"
             git add deploy/helm/pulse/Chart.yaml
             git commit -m "Auto-update Helm chart version to $VERSION"
-            git push
+            git pull --rebase origin main
+            git push origin main
           fi
 
       - name: Validate Helm chart