Improved unit test for creating database (#1179)

## Changes
Fix failing test caused by change in underlying implementation

### Linked issues
Resolves #1174 

### Functionality 

- [ ] added relevant user documentation
- [ ] added new CLI command
- [ ] modified existing command: `databricks labs ucx ...`
- [ ] added a new workflow
- [ ] modified existing workflow: `...`
- [ ] added a new table
- [ ] modified existing table: `...`

### Tests

- [ ] manually tested
- [ ] added unit tests
- [ ] added integration tests
- [ ] verified on staging environment (screenshot attached)

Fixed unit test

Author: ericvergnaud

tests/unit/test_install.py

@@ -224,7 +224,11 @@ def test_create_database(ws, caplog, mock_installation, any_prompt):
     )
 
     with pytest.raises(BadRequest) as failure:
-        workspace_installation.run()
+        try:
+            workspace_installation.run()
+        except ManyError as e:
+            assert len(e.errs) == 1
+            raise e.errs[0]
 
     assert "Kindly uninstall and reinstall UCX" in str(failure.value)