Coverage remained the same at 89.476% when pulling8a56d67 on bnavigator:py39-float-tests intoe81f648 on python-control:master.

StateSpace matrices are always of dtype float (or complex, if#484 ever gets adopted), so comparing them to integer reference values can have a float precision error.

Not necessarily true for TransferFunction right now, but keep the same logic.

Merging now, so that other PRs can be checked properly again.