Add a source_module_name to android_app

For multiple mainline prebuilts, we will have multiple versioned
prebuilt apps in the tree. The soong name of these prebuilts will have a
version prefix to prevent name collisions (e.g. MyGoogleApp.v2).

This CL introduces a source_module_name property in android_app_imoprt.
This property will be used for the following
1. Determining installation path. This should be
/system/app/MyGoogleApp/MyGoogleApp.apk
and not
/system/app/MyGoogleApp.v2/MyGoogleApp.apk
(filename prop determines the filename and not the dir name)

2. Preventing duplicate installation rules: This property will be used
   to create a dependency to the source app, and call HideFromMake on
   all the unflagged apps

Test: presubmits
Test: locally # Created CaptivePortalLoginGoogle.v2 and selected it
using one of the RELEASE_APEX_CONTRIBUTION_* flags

Bug: 326995930
Change-Id: If4ab9f9bd295117c96eb062cf3b3d2efc8bfed12