Fix typeArguments array not being cloned when resolving ParameterizedType with changed owner

[TBlueF]

Purpose

This PR fixes an inconsistency in $Gson$Types#resolve() where the ParameterizedType#getActualTypeArguments() array is only cloned when the resolved owner-type has not changed from the original owner-type.

Description

In most cases this is a non-issue, as usually all ParameterizedType implementations clone the array themselves when invoking the getActualTypeArguments() getter. However, this is not guaranteed.
Cloning the array only when the owner-type didn't change seems like an inconsistency and an oversight, so this PR is trying to fix that.

Checklist

• New code follows the Google Java Style Guide
  This is automatically checked by mvn verify, but can also be checked on its own using mvn spotless:check.
  Style violations can be fixed using mvn spotless:apply; this can be done in a separate commit to verify that it did not cause undesired changes.
• If necessary, new public API validates arguments, for example rejects null
• New public API has Javadoc
  • Javadoc uses @since $next-version$
    ($next-version$ is a special placeholder which is automatically replaced during release)
• If necessary, new unit tests have been added
  • Assertions in unit tests use Truth, see existing tests
  • No JUnit 3 features are used (such as extending class TestCase)
  • If this pull request fixes a bug, a new test was added for a situation which failed previously and is now fixed
• mvn clean verify javadoc:jar passes without errors

[eamonnmcmanus]

Thanks! I agree that the original code seems a bit suspect and this is the cleanest way to fix it.