[installer-tests] fix azure authentication

Author: nandajavarma

install/tests/Makefile

@@ -52,6 +52,7 @@ gcp-kubeconfig:
 
 ## azure-kubeconfig: Get the kubeconfig configuration for Azure AKS
 azure-kubeconfig:
+az login --service-principal -u $$ARM_CLIENT_ID -p $$ARM_CLIENT_SECRET --tenant $$ARM_TENANT_ID
 export KUBECONFIG=${KUBECONFIG} && \
 export resource=$$(echo "$$TF_VAR_TEST_ID" | sed "s/[\\W\\-]//g") && \
 az aks get-credentials --name test-cluster-$$resource --resource-group sh-test-$$resource --file ${KUBECONFIG} || echo "No cluster present"