Update purge workflow_dispatch logic (radius-project#7646)

# Description

The check for creating issues was creating issues even on successes.
Tested this with manual runs and they're not creating issues

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Fixes: radius-project#7645

---------

Signed-off-by: sk593 <shruthikumar@microsoft.com>

.github/workflows/purge-test-resources.yaml

@@ -105,7 +105,7 @@ jobs:
     name: Create issue for failing purge test resources run
     needs: [purge_ghcr_dev, purge_azure_resources]
     runs-on: ubuntu-latest
-    if: always() && ${{ github.event_name != 'workflow_dispatch' }} && (needs.purge_ghcr_dev.result == 'failure' || needs.purge_azure_resources.result == 'failure')
+    if: failure() && ${{ github.event_name != 'workflow_dispatch' }}
     steps:
       - uses: actions/github-script@v7
         with: