Add temporary login for expired auth (#7491)

# Description

Long-running tests have started to fail due to the az login
authentication expiring. Based on the error message (see linked issue),
the authentication is only valid for 5 minutes. This seems to be a known
issue [based on discussion
here](Azure/azure-cli#28708 (comment))
but there's no fix so adding this temporary workaround until there's a
way to extend the time the auth is valid.


## Type of change

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#7490

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Fixes: #issue_number

Signed-off-by: sk593 <[email protected]>

.github/workflows/long-running-azure.yaml

@@ -485,6 +485,12 @@ jobs:
         if: failure()
         run: |
           echo ":x: functional test failed." >> $GITHUB_STEP_SUMMARY
+      - name: Login to Azure
+        uses: azure/login@v2
+        with:
+          client-id: ${{ secrets.AZURE_SP_TESTS_APPID }}
+          tenant-id: ${{ secrets.AZURE_SP_TESTS_TENANTID }}
+          subscription-id: ${{ secrets.AZURE_SUBSCRIPTIONID_TESTS }}
       - name: Delete azure resource group - ${{ env.AZURE_TEST_RESOURCE_GROUP }}
         if: always()
         run: |