Enable Gradle Build cache and building modules in parallel

[WhosNickDoglio]

Gradle supports building modules in parallel as well as avoiding rebuilding modules when nothing in them changes via the build cache feature.

This PR enables both of those features. Right now any improvements from these features is pretty minimal but as the project grows and potentially moduralizes more these provide a large benefit.

[0xtmphey]

Just to add some context: multi-module KMP projects kinda sucks on iOS now:

• Space usage grows significantly with each added gradle module (it creates native compilation target for each module)
• Build experience is bad. For some reason, each gradle module takes lots of memory to compile to native and if you enable parallel build, you usually end up in OOM state.

But the above just FYI, in general cache and parallel options are must-haves