Fix up + improve CI test reporting workflow

.github/workflows/report-nunit.yml

@@ -5,33 +5,40 @@
 name: Annotate CI run with test results
 on:
   workflow_run:
-    workflows: ["Continuous Integration"]
+    workflows: [ "Continuous Integration" ]
     types:
       - completed
-permissions: {}
+
+permissions:
+  contents: read
+  actions: read
+  checks: write
+
 jobs:
   annotate:
-    permissions:
-      checks: write # to create checks (dorny/test-reporter)
-
     name: Annotate CI run with test results
     runs-on: ubuntu-latest
     if: ${{ github.event.workflow_run.conclusion != 'cancelled' }}
-    strategy:
-       fail-fast: false
-       matrix:
-          os:
-            - { prettyname: Windows }
-            - { prettyname: macOS }
-            - { prettyname: Linux }
-          threadingMode: ['SingleThread', 'MultiThreaded']
     timeout-minutes: 5
     steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          repository: ${{ github.event.workflow_run.repository.full_name }}
+          ref: ${{ github.event.workflow_run.head_sha }}
+
+      - name: Download results
+        uses: actions/download-artifact@v4
+        with:
+          pattern: osu-test-results-*
+          merge-multiple: true
+          run-id: ${{ github.event.workflow_run.id }}
+          github-token: ${{ github.token }}
+
       - name: Annotate CI run with test results
         uses: dorny/[email protected]
         with:
-          artifact: osu-test-results-${{matrix.os.prettyname}}-${{matrix.threadingMode}}
-          name: Test Results (${{matrix.os.prettyname}}, ${{matrix.threadingMode}})
+          name: Results
           path: "*.trx"
           reporter: dotnet-trx
           list-suites: 'failed'