util: add inspect suffix to BigInt64Array elements

This commit updates `util.inspect` to add an `n` suffix to BigInts that
appear in BigInt64Arrays. BigInts are formatted with an `n` suffix in
most cases, but this did not occur in BigInt64Arrays due to an apparent
oversight where the implementation of `inspect` for typed arrays assumed
that all typed array elements are numbers.

PR-URL: https://github.com/nodejs/node/pull/21499


Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Yuta Hiroto <hello@hiroppy.me>