Avoid loading TimeZones at build time

[IanButterworth]

It's unusual to load the package itself during build time

TimeZones.jl/deps/build.jl

Line 1 in ae1e583

using TimeZones: build

This doesn't play well with the new pkg parallel precompilation as it forces TimeZones and all its dependencies to be precompiled in series (load-time precompilation) slowly during build time.
So while pkg is reporting building TimeZones it's probably actually spending a bunch of that time precompiling.

It may be a contributing factor in #331 given it might be causing some things to happen out of order?

[omus]

In PR #441 the deps/build.jl was removed so this is no longer an issue. Included in TimeZones release 1.12