tests: re-enable pretty-std-collections on macOS
Fixes#78665.
I made some small modifications to this test so that it would pass for me locally (though I was only able to test using lldb without built-in Rust support, but that seems to be the mode in which it would fail). I ran it a few hundred times with stage one and stage two to see if I could re-produce the spurious failures that were being reported in #78665 and couldn't. From the discussion in #78665, it seemed like this was related to Xcode versions and could be reproduced locally fairly easily. It's been a couple years since this was disabled so a lot has changed. If this starts failing spuriously again then we can disable it and I can look into that.
r? `@wesleywiser` (discussed in wg-debugging's triage meeting)
Combining revisions with only-arch allows specifying
that a test only applies to a handful of targets.
This allows removing a large amount of repetition
in the test suite for tests that do not benefit.
The revisions are suboptimal for this for some tests,
so they aren't preferred in those cases.
Stabilize debugger_visualizer
This stabilizes the `debugger_visualizer` attribute (#95939).
* Marks the `debugger_visualizer` feature as `accepted`.
* Marks the `debugger_visualizer` attribute as `ungated`.
* Deletes feature gate test, removes feature gate from other tests.
Closes#95939
Like #107044, this will let us track compatibility with LLVM 16 going
forward, especially after we eventually upgrade our own to the next.
This also drops `tidy` here and in `x86_64-gnu-llvm-15`, syncing with
that change in #106085.
