Method remove_child returns a ValueError with client property object

[SethDocherty]

When using the pystac_client.Client object that's assigned to the client property in the Web3 class, I'm unable to use the remove_child() method inherited via the pystac.Catalog object.

The following method filters out collections from a STACObject

def filter_catalog(stac_object, collections_to_keep: List[str]) -> None:
    child_ids = [child.id for child in stac_object.get_children()]
    if not collections_to_keep:
        for col in child_ids:
            stac_object.remove_child(col)
    else:
        # Remove any collections that are not in the keep_collections list
        for col in child_ids:
            if col not in collections_to_keep:
                stac_object.remove_child(col)

Using the client property form the Web3 class:

test_client = client.Web3(stac_endpoint=<STAC URL>)
filter_catalog(test_client.client, [<COLLECTION ID>])

returns the following error:

  File "./.../.venv/lib/python/site-packages/pystac_client/collection_client.py", line 102, in set_root
    raise ValueError(
ValueError("`CollectionClient.root` must be set")

If I instead create a new STACObject instead of using the existing one, I do not get an error:

stac_obj = pystac.Catalog.from_file(tmp_client.stac_endpoint)
filter_catalog(test_client.client, [<COLLECTION ID>])

References:

stac-utils/pystac-client#706