Don't import CuraApplication if not type checking

Otherwise we'll get unnecessary import loops here.

Contributes to issue CURA-8609.

cura/UltimakerCloud/UltimakerCloudScope.py

@@ -1,9 +1,15 @@
+# Copyright (c) 2021 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
+
 from PyQt5.QtNetwork import QNetworkRequest
 
 from UM.Logger import Logger
 from UM.TaskManagement.HttpRequestScope import DefaultUserAgentScope
 from cura.API import Account
-from cura.CuraApplication import CuraApplication
+
+from typing import TYPE_CHECKING
+if TYPE_CHECKING:
+    from cura.CuraApplication import CuraApplication
 
 
 class UltimakerCloudScope(DefaultUserAgentScope):
@@ -12,7 +18,7 @@ class UltimakerCloudScope(DefaultUserAgentScope):
     Also add the user agent headers (see DefaultUserAgentScope).
     """
 
-    def __init__(self, application: CuraApplication):
+    def __init__(self, application: "CuraApplication"):
         super().__init__(application)
         api = application.getCuraAPI()
         self._account = api.account  # type: Account