add functional test results to artifacts (radius-project#7583)

# Description
Add functional test results as an artifact so we can download it. 
Currently, rerun erases a functional test run's result and there is no
easy way to download/process the results.

Sample artifact that is produced after adding these changes is in the
summary of [Functional tests · radius-project/radius@65bed3d
(github.com)](https://github.com/radius-project/radius/actions/runs/9023474283)

Name of the artifact is functional_test_results

## Type of change

- This pull request adds or changes features of Radius and has an
approved issue (issue link required).

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Fixes: radius-project#6727

---------

Signed-off-by: nithyatsu <[email protected]>

.github/actions/process-test-results/action.yaml

@@ -56,6 +56,7 @@ runs:
       uses: EnricoMi/publish-unit-test-result-action@v2
       if: always()
       with:
+        check_name: ${{ inputs.test_group_name }}
         files: |
           ${{ inputs.result_directory }}/processed/*.xml
     - name: 'Upload ${{ inputs.test_group_name }} Results'

.github/workflows/functional-test.yaml

@@ -546,6 +546,8 @@ jobs:
         run: |
           # Ensure rad cli is in path before running tests.
           export PATH=$GITHUB_WORKSPACE/bin:$PATH
+          # Make directory to capture functional test results
+          mkdir -p ./dist/functional_test 
           cd $GITHUB_WORKSPACE
 
           which rad || { echo "cannot find rad"; exit 1; }
@@ -575,6 +577,15 @@ jobs:
           BICEP_RECIPE_REGISTRY: ${{ env.BICEP_RECIPE_REGISTRY }}
           BICEP_RECIPE_TAG_VERSION: ${{ env.BICEP_RECIPE_TAG_VERSION }}
           GH_TOKEN: ${{ steps.get_installation_token.outputs.token }}
+          GOTESTSUM_OPTS: '--junitfile ./dist/functional_test/results.xml'
+      - name: Process Functional Test Results
+        uses: ./.github/actions/process-test-results
+        # In case of failure, upload functional_test_results to artifacts so that they are not erased by subsequent runs.
+        if: failure() && github.repository == 'radius-project/radius'
+        with:
+          test_group_name: 'Functional Tests - ${{ matrix.name }}'
+          artifact_name: 'functional_test_results_${{ matrix.name }}'
+          result_directory: 'dist/functional_test/' 
       - uses: azure/setup-kubectl@v4
         if: always()
         with: