Cleanup self-hosted runners: switch Azure login logic to our own

We now have our own simple workflow to log into Azure, using "az login". As we're moving way from things like the Azure CLI, let's also start using our own login script instead.

Signed-off-by: Dennis Ameling <[email protected]>

.github/workflows/cleanup-self-hosted-runners.yml

@@ -21,38 +21,16 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
-    - name: Process Azure credentials
-      uses: actions/github-script@v7
-      env:
-        AZURE_CREDENTIALS: ${{ secrets.AZURE_CREDENTIALS }}
+    - name: Azure Login
+      uses: ./.github/workflows/azure-login
       with:
-        script: |
-          if (!process.env.AZURE_CREDENTIALS) {
-            core.setFailed('The AZURE_CREDENTIALS secret is required.')
-            process.exit(1)
-          }
-          
-          const azureCredentials = JSON.parse(process.env.AZURE_CREDENTIALS)
-          const {clientId, clientSecret, tenantId, subscriptionId} = azureCredentials
-
-          core.setSecret(clientId)
-          core.exportVariable('AZURE_CLIENT_ID', clientId)
-
-          core.setSecret(clientSecret)
-          core.exportVariable('AZURE_CLIENT_SECRET', clientSecret)
-
-          core.setSecret(tenantId)
-          core.exportVariable('AZURE_TENANT_ID', tenantId)
+        credentials: ${{ secrets.AZURE_CREDENTIALS }}
 
-          core.setSecret(subscriptionId)
-          core.exportVariable('AZURE_SUBSCRIPTION_ID', subscriptionId)
     - name: Discover VMs to delete
       env:
         GH_APP_ID: ${{ secrets.GH_APP_ID }}
         GH_APP_PRIVATE_KEY: ${{ secrets.GH_APP_PRIVATE_KEY }}
       run: |
-        az login --service-principal -u ${{ env.AZURE_CLIENT_ID }} -p ${{ env.AZURE_CLIENT_SECRET }} --tenant ${{ env.AZURE_TENANT_ID }}
-        az account set --subscription ${{ env.AZURE_SUBSCRIPTION_ID }}
         active_vms=$(az vm list -g ${{ secrets.AZURE_RESOURCE_GROUP }} | jq -c '.[] | {name,timeCreated}')
         current_time=$(date +%s)
         one_hour_ago=$(($current_time - 3600))