Makefile.maker.yaml: remove Coveralls

This is required because of
<sapcc/go-makefile-maker#351>.

Author: majewsky

.github/workflows/ci.yaml

@@ -33,6 +33,24 @@ jobs:
         with:
           check-latest: true
           go-version: 1.24.6
+  code_coverage:
+    name: Code coverage report
+    if: github.event_name == 'pull_request'
+    needs:
+      - test
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v5
+      - name: Post coverage report
+        uses: fgrosse/go-coverage-report@v1.2.0
+        with:
+          coverage-artifact-name: code-coverage
+          coverage-file-name: cover.out
+    permissions:
+      actions: read
+      contents: read
+      pull-requests: write
   test:
     name: Test
     needs:
@@ -52,10 +70,8 @@ jobs:
           sudo apt-get install -y --no-install-recommends postgresql-17
           export PATH=/usr/lib/postgresql/17/bin:$PATH
           make build/cover.out
-      - name: Upload coverage report to Coveralls
-        env:
-          COVERALLS_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          GIT_BRANCH: ${{ github.head_ref }}
-        run: |
-          go install github.com/mattn/goveralls@latest
-          goveralls -service=github -coverprofile=build/cover.out
+      - name: Archive code coverage results
+        uses: actions/upload-artifact@v4
+        with:
+          name: code-coverage
+          path: build/cover.out

Makefile.maker.yaml

@@ -6,7 +6,6 @@ metadata:
 githubWorkflow:
   ci:
     enabled: true
-    coveralls: true
 
 golang:
   autoupdateableDeps: ^github.com/(?:sapcc|sap-cloud-infrastructure)/