test: Skip test if console log is None (#5188)

In the recent pycloudlib bump, Azure's console_log call went from
raising NotImplementedError to returning None if the boot diagnostic
log hasn't been initialized.

tests/integration_tests/util.py

@@ -325,6 +325,8 @@ def get_console_log(client: "IntegrationInstance"):
         console_log = client.instance.console_log()
     except NotImplementedError:
         pytest.skip("NotImplementedError when requesting console log")
+    if console_log is None:
+        pytest.skip("Console log has not been setup")
     if console_log.lower().startswith("no console output"):
         pytest.fail("no console output")
     return console_log