Always transform Inlined.call in CheckUnused

[som-snytt]

Fixes #23201

Previously, CheckUnused transformed the call tree of an Inlined node only after typer (and not after inlining), but inlining also results in non-trivial call trees.

Needs a minimized test, where an import is required for expansion but is unused at typer.

[som-snytt]

Still needs a test.

[tgodzik]

Still needs a test.

Do you need help minimizing it ? I can try to take a look

[som-snytt]

I'll take another swing at the test. Some combination of derives, inline given, and a macro.

I confirmed the second example on the ticket is similar; their workaround was to make the given not inline.

[som-snytt]

Superseded by https://github.com/scala/scala3/pull/24043