inspector,vm: remove --eval wrapper

Report the actual source code when running with `--eval` and
`--inspect-brk`, by telling the vm module to break on the
first line of the script being executed rather than wrapping
the source code in a function.

PR-URL: https://github.com/nodejs/node/pull/25832


Reviewed-By: Eugene Ostroukhov <eostroukhov@google.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>