fix(cdk/schematics): use workingDirectory smart provider in path option

The Angular CLI, handles options with both name and format `path` as a special case. This behaviour has been deprecated and instead the `workingDirectory` smart provider should be used instead. Currently, when not using the provider a deprecation warning will be issue.

See: angular/angular-cli#23212

Author: alan-agius4

src/cdk/schematics/ng-generate/drag-drop/schema.json

@@ -7,6 +7,9 @@
     "path": {
       "type": "string",
       "format": "path",
+      "$default": {
+        "$source": "workingDirectory"
+      },
       "description": "The path to create the component.",
       "visible": false
     },