Turn hilt-extensions into regular java library

[matejdro]

Currently, hilt-extensions is an android library, which prevents it from being used in non-android modules.

From what I can see, this library only contains a bunch of annotations, it has no Android references. Could we turn it into regular java library?

[sczerwinski]

These extensions could be useful for Dagger projects as well. Unfortunately, I'm a bit busy with other work right now.

Would you like to create a pull request with these changes, @matejdro?

[matejdro]

Yes, I can try my hand at the pull request. But I can't promise on any dates, it might take a while.