child_process: swallow errors in internal communication

Much like with NODE_HANDLE_ACK, the internal protocol for communication
about the sent socket should not expose its errors to the users when
those async calls are not initiated by them.

PR-URL: https://github.com/nodejs/node/pull/21108


Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>