commands: propertize WestCommand.requires_installation

This makes it impossible for these two fields to get out of sync.

Signed-off-by: Martí Bolívar <marti.bolivar@nordicsemi.no>

src/west/commands.py

@@ -104,10 +104,14 @@ class WestCommand(ABC):
             self.requires_workspace = requires_installation
         else:
             self.requires_workspace = requires_workspace
-        self.requires_installation = self.requires_workspace
         self.topdir = None
         self.manifest = None
 
+    @property
+    def requires_installation(self) -> bool:
+        '''Deprecated property alias for self.requires_workspace.'''
+        return self.requires_workspace
+
     def run(self, args, unknown, topdir, manifest=None):
         '''Run the command.