`test_path_dependency_runnables` is flaky

[lnicola]

[>2520.000s] rust-analyzer::slow-tests test_path_dependency_runnables

https://github.com/rust-lang/rust-analyzer/actions/runs/18182591478/job/51761233840?pr=20776
https://github.com/rust-lang/rust-analyzer/actions/runs/18186496833/job/51771749148?pr=20782

[lnicola]

I can't reproduce this locally using while :; do RUN_SLOW_TESTS=1 cargo test -p rust-analyzer test_path_dependency_runnables; done.