Enable TUnit test report artifact upload in GitHub Actions (#902)

TUnit can automatically upload HTML test reports as workflow artifacts
and link them in the step summary when running in GitHub Actions — but
only if `ACTIONS_RUNTIME_TOKEN` is available to the shell process, which
it isn't by default (it's only exposed inside JS/Docker action
handlers).

## Changes

- Added an **"Expose GitHub Actions Runtime"** step using
`actions/github-script@v7` immediately before the `dotnet test` step in
both workflow files:
  - `.github/workflows/PR-Build-And-Test.yml`
  - `.github/workflows/Build-Test-And-Deploy.yml`

```yaml
- name: Expose GitHub Actions Runtime
  uses: actions/github-script@v7
  with:
    script: |
      core.exportVariable('ACTIONS_RUNTIME_TOKEN', process.env['ACTIONS_RUNTIME_TOKEN']);
      core.exportVariable('ACTIONS_RESULTS_URL', process.env['ACTIONS_RESULTS_URL']);

- name: Run .NET Tests
  run: dotnet test ...
```

With this in place, TUnit will upload the test report as a workflow
artifact and add a direct link to it in the step summary on each run.

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Author: Copilot

.github/workflows/Build-Test-And-Deploy.yml

@@ -43,6 +43,13 @@ jobs:
       - name: Build with dotnet
         run: dotnet build -p:ContinuousIntegrationBuild=True -p:ReleaseDateAttribute=True --configuration Release --no-restore
 
+      - name: Expose GitHub Actions Runtime
+        uses: actions/github-script@v7
+        with:
+          script: |
+            core.exportVariable('ACTIONS_RUNTIME_TOKEN', process.env['ACTIONS_RUNTIME_TOKEN']);
+            core.exportVariable('ACTIONS_RESULTS_URL', process.env['ACTIONS_RESULTS_URL']);
+
       - name: Run .NET Tests
         run: dotnet test --no-build --configuration Release
 

.github/workflows/PR-Build-And-Test.yml

@@ -34,6 +34,13 @@ jobs:
       - name: Build with dotnet
         run: dotnet build --configuration Release --no-restore /p:AccessToNugetFeed=false
 
+      - name: Expose GitHub Actions Runtime
+        uses: actions/github-script@v7
+        with:
+          script: |
+            core.exportVariable('ACTIONS_RUNTIME_TOKEN', process.env['ACTIONS_RUNTIME_TOKEN']);
+            core.exportVariable('ACTIONS_RESULTS_URL', process.env['ACTIONS_RESULTS_URL']);
+
       - name: Run .NET Tests
         run: dotnet test --no-build --configuration Release --report-trx --coverage --results-directory ${{ runner.temp }}