Coverage instruments closure bodies in macros (not the macro body)

Fixes: #84884

This solution might be considered a compromise, but I think it is the
better choice.

The results in the `closure.rs` test correctly resolve all test cases
broken as described in #84884.

One test pattern (in both `closure_macro.rs` and
`closure_macro_async.rs`) was also affected, and removes coverage
statistics for the lines inside the closure, because the closure
includes a macro. (The coverage remains at the callsite of the macro, so
we lose some detail, but there isn't a perfect choice with macros.

Often macro implementations are split across the macro and the callsite,
and there doesn't appear to be a single "right choice" for which body
should be covered. For the current implementation, we can't do both.

The callsite is most likely to be the preferred site for coverage.

I applied this fix to all `MacroKinds`, not just `Bang`.

I'm trying to resolve an issue of lost coverage in a
`MacroKind::Attr`-based, function-scoped macro. Instead of only
searching for a body_span that is "not a function-like macro" (that is,
MacroKind::Bang), I'm expanding this to all `MacroKind`s. Maybe I should
expand this to `ExpnKind::Desugaring` and `ExpnKind::AstPass` (or
subsets, depending on their sub-kinds) as well, but I'm not sure that's
a good idea.

I'd like to add a test of the `Attr` macro on functions, but I need time
to figure out how to constract a good, simple example without external
crate dependencies. For the moment, all tests still work as expected (no
change), this new commit shouldn't have a negative affect, and more
importantly, I believe it will have a positive effect. I will try to
confirm this.

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