Auto merge of #98817 - the8472:dont-optimize-ui-tests, r=Mark-Simulacrum

Only obey optimize-tests flag on UI tests that are run-pass

stage1 UI tests walltime on my machine:

```
optimize-tests = false, master
25.98s

optimize-tests = true, master
34.69s

optimize-tests = true, patched
28.79s
```

Effects:

- faster UI tests
- llvm asserts get exercised less on build-pass tests
- the difference between opt and nopt builds shrinks a bit
- aux libs don't get optimized since they don't have a pass mode and almost never have explicit compile flags

diff --cc src/tools/compiletest/src/runtest.rs
Simple merge