fix: added types to exec & tc_properties_get_tc_host

[Dandiggas]

#557 - trying to solve this issue by adding types.

[errordeveloper]

this LGTM overall, thanks @Dandiggas!

[errordeveloper]

@kiview could you please approve the workflows to run?

[alexanderankin]

We'll take a look

[alexanderankin]

yep so we support python 3.9 for now so cant use the pipe syntax for typing.Union - but the other type is indeed wrong so we could merge a pr that just fixes a single type, would probably prefer a PR that fixes types more comprehensively like #504 - if you want to provide feedback on that branch, that could help it along - it was only not merged because i was not confident in 100% of the choices made in there at the time.

ill leave this open in case you want to replace with from typing import Union

[Dandiggas]

@alexanderankin Now supports python 3.9, please review when possible

[alexanderankin]

thank you for the contribution! if you are interested in improving typing in this library are other types that I have started but did not feel confident enough to merge #504