Flyimport completions for `Write` only show `std::fmt::Write`

[Veykril]

This should also show std::io::Write, the auto import assist works correctly here

[Veykril]

Something in import_map::search_dependencies is broken here, the trait is inthe import map (with two import paths), yet we don't record it when looking for it in import_map::search_dependencies...

[Veykril]

This is the same root cause as #15845 #16080

[Veykril]

#16107