multi-feature-module uses api instead of implementation

[mustafaberkaymutlu]

The Android documentation says feature modules should use "implementation" instead of "api" while adding base module in their dependencies.

"The two individual feature modules use the implementation project expression within their dependencies block"

All samples that have base modules use "implementation" but multi-feature-module sample uses "api" in here and here.

[keyboardsurfer]

Thanks for reporting this issue. It'll be fixed with the next sample release.

[keyboardsurfer]

Shipped with today's release.