Update catalog.py

[chrhenry]

Fix for the following error

File /databricks/python/lib/python3.10/site-packages/databricks/sdk/service/catalog.py:2117, in UpdatePermissions.as_dict(self) 2116 if self.full_name: body['full_name'] = self.full_name -> 2117 if self.securable_type: body['securable_type'] = self.securable_type.value 2118 return body

AttributeError: 'str' object has no attribute 'value'

Changes

Tests

• [ ] make test run locally
• [ ] make fmt applied
• [ ] relevant integration tests applied