test: add wasi test for symlink() and readlink()

This test provides missing coverage for __wasi_path_symlink()
and __wasi_path_readlink().

PR-URL: https://github.com/nodejs/node/pull/31403


Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>