Fix taxonomy term creation

[Kingdutch]

parent may be empty if multiple taxonomies are created in a single Given block.

Additionally id is not the right base field for the query but it should be name.

Finally the entityQuery does not return loaded entities but returns IDs so calling ->id() on it will break as well.

Fixes #259

[aaron-capellic]

Thank you, this is working for me.

[jhedstrom]

Thank you!