ci: collate codecov reports before uploading

Currently due to flake partial reports are submitting which results in
constant fluctuation of coverage reports.
Change: First collect coverage and if all builds pass then submit it.

.github/workflows/server-tests-mariadb.yml

@@ -118,10 +118,23 @@ jobs:
           CI_BUILD_ID: ${{ github.run_id }}
           ORCHESTRATOR_URL: http://test-orchestrator.frappe.io
 
+      - name: Upload coverage data
+        uses: actions/upload-artifact@v3
+        with:
+          name: coverage-${{ matrix.container }}
+          path: /home/runner/frappe-bench/sites/coverage.xml
+
+  coverage:
+    name: Coverage Wrap Up
+    needs: test
+    runs-on: ubuntu-latest
+    steps:
+      - name: Download artifacts
+        uses: actions/download-artifact@v3
+
       - name: Upload coverage data
         uses: codecov/codecov-action@v2
         with:
           name: MariaDB
           fail_ci_if_error: true
-          files: /home/runner/frappe-bench/sites/coverage.xml
           verbose: true

codecov.yml

@@ -21,7 +21,6 @@ coverage:
 comment:
   layout: "diff, files"
   require_changes: true
-  after_n_builds: 3
 
 ignore:
   - "erpnext/demo"