Additional typing fixes

CURA-7473

cura/API/Account.py

@@ -68,7 +68,7 @@ class Account(QObject):
         self._sync_state = SyncState.IDLE
         self._manual_sync_enabled = False
         self._update_packages_enabled = False
-        self._update_packages_action = None  # type: Callable
+        self._update_packages_action = None  # type: Optional[Callable]
         self._last_sync_str = "-"
 
         self._callback_port = 32118

plugins/Toolbox/src/CloudSync/CloudPackageChecker.py

@@ -110,11 +110,11 @@ class CloudPackageChecker(QObject):
             # scenario:
             # 1. user subscribes to a package
             # 2. dismisses the license/unsubscribes
-            # 3. subscribes to the same packafe again
+            # 3. subscribes to the same package again
             # in this scenario we want to notify the user again. To capture that there was a change during
             # step 2, we clear the last_notified after step 2. This way, the user will be notified after
             # step 3 even though the list of packages for step 1 and 3 are equal
-            self._last_notified_packages = None
+            self._last_notified_packages = set()
 
         if package_discrepancy:
             account = self._application.getCuraAPI().account