Fix documentation for using AutoValue with Gradle.
Fix documentation for using AutoValue with Gradle.

compileOnlyApi only works with the Java Library plugin.
api works with both the Java Library and Android plugins.
compileOnly seems to have always existed and appears to be exactly the same as compileOnlyApi,
aside from transitively exporting the dependency to consumers
(i.e., compileOnlyApi adds to compileOnly the same way api adds to compile).

Valid dependency configurations can be found here:
- [Java plugin](https://docs.gradle.org/current/userguide/java_plugin.html#tab:configurations)
- [Java Library plugin](https://docs.gradle.org/current/userguide/java_library_plugin.html#sec:java_library_configurations_graph)
- [Android plugin](https://developer.android.com/studio/build/dependencies#dependency_configurations)

Fixes #1220.

RELNOTES=n/a
PiperOrigin-RevId: 420288492

eamonnmcmanus/auto,eamonnmcmanus/auto,google/auto,google/auto,eamonnmcmanus/auto,google/auto