zfs: fix property handling and map '-' as PropertySource.NONE

src/simplezfs/types.py

@@ -132,7 +132,7 @@ class PropertySource(str, Enum):
             return PropertySource.TEMPORARY
         elif val == 'received':
             return PropertySource.RECEIVED
-        elif val == 'none':
+        elif val == 'none' or val == '-':
             return PropertySource.NONE
         else:
             raise ValueError(f'Value {value} is not a valid PropertySource')

src/simplezfs/zfs.py

@@ -486,7 +486,7 @@ class ZFS:
 
         # check the syntax of the properties
         if properties is not None:
-            for k, v in properties:
+            for k, v in properties.items():
                 validate_native_property_name(k)
                 validate_property_value(v)