test: remove obsolete WASI test

test-wasi-binding.js was added during the initial WASI
development, but it is now considered obsolete. It also does
not provide any additional test coverage. This commit removes
it.

PR-URL: #30980
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Rich Trott <rtrott@gmail.com>

Author: cjihrig