Remove --with-tzpath setting

[isuruf]

The conda location is supposed to be appended instead of overriding.

cc @ocefpaf, @mbargull

[mbargull]

Why not prepend? (And if we prepend, we could as well override as currently is.)

[isuruf]

I can't remember the reason, but there was some discussion as to what to do. cc @ocefpaf, @mingwandroid

[ocefpaf]

Why not prepend? (And if we prepend, we could as well override as currently is.)

Yep. We could pre-pended but then that would not really make a difference b/c our path would always be present since our tzdata is a Python dependency.

The pep does suggests to append but, b/c we do have our own tzdata, overriding it not that bad. That was modeled after a build without tzdata as a dependency or as an optional dependency.