streams_events.rs module doc-comment still lists "validator" after its FFI declarations were removed #10726

Cosmetic, one line, filed so it doesn't become folklore.

crates/perry-codegen/src/runtime_decls/stdlib_ffi/streams_events.rs's module doc-comment (line 2) still lists
"validator" in its summary of what the module declares, although the validator FFI declarations were removed.

This predates PR #10690's rebase — it was already true in that PR's original commit — so it was deliberately left
alone there rather than widening the diff, since fixing it inside a rebase would have made the diff misrepresent
what the rebase did.

Worth sweeping the same file for other stale names as the binding-removal campaign continues: several removals
have now taken FFI declarations out of shared stdlib_ffi modules without updating the prose at the top, and a
doc-comment that lists packages which no longer exist is the kind of thing that quietly misleads someone grepping
for where a binding lives.

Context: part of the work removing Perry's hand-written Rust reimplementations of npm packages in favour of
compiling the real ones.