Gradle builds target dependencies for target modules with no source after change.

[fuzzyweapon]

EX:

• acornui-build-tasks only has source for jvm, but in order to use the MPP plugin, we are currently defining a js target as well.
• acornui-build-tasks-js has the kotlin-stdlib-js as a dependency.
• actual -jvm dependencies are declared in the common target

1. Make a change in jvm src.
2. Execute publishToLocalMaven from acornui-build-tasks.
3. Observe gradle calling the acornui-core-js compile task.

Current speculation is it's unclear whether we can fix this in a clean way. The possible solution below may not be fully supported and requires us to do some things I wouldn't be happy for us to own in the long run, and I think regardless, we'll want to escalate something with jetbrains about smoothing this out.

SPIKE: We can try specifying specific target configurations in our project dependency declarations for only the targets we have actual source for, but this is untested. It's unclear how this might interfere with other aspects of the build or if it will even be fully compatible with the MPP plugin.

• File any long term jb bugs necessary