build: fix non-fast-forward push in publish_coverage_pr

PR-URL: #13393
Reviewed-by: Athan Reines <kgryte@gmail.com>

Author: Planeshifter

.github/workflows/publish_coverage_pr.yml

@@ -157,8 +157,11 @@ jobs:
         run: |
           cd ./www-test-code-coverage
           BRANCH_NAME="pr-$PR_NUMBER"
-          git fetch origin "$BRANCH_NAME" || true
-          git checkout "$BRANCH_NAME" || git checkout -b "$BRANCH_NAME"
+          if git fetch origin "$BRANCH_NAME"; then
+            git checkout -B "$BRANCH_NAME" FETCH_HEAD
+          else
+            git checkout -b "$BRANCH_NAME"
+          fi
 
           # Remove all directories except .github and .git from branch:
           find . -mindepth 1 -maxdepth 1 -type d -not -name '.github' -not -name '.git' -exec git rm -rf {} + || true