benchmark: fix hanging dgram/array-vs-concat.js

[Trott]

Checklist

• make -j4 test (UNIX), or vcbuild test nosign (Windows) passes
• tests and/or benchmarks are included
• commit message follows commit guidelines

Affected core subsystem(s)

bencmark, dgram

Description of change

Exit process so benchmark can continue.

process.exit() was removed previously at 83432bf#diff-1cc47d7eb19f32771e7d3f6d813eb92cL242

This change adds it back, but only in this benchmark and not in benchmark/common.js.

/cc @mscdex

[mscdex]

I'm guessing it wouldn't be sufficient to just close the socket to allow the process to exit naturally or ?

[Trott]

@mscdex To do that you need to handle stopping the firehose to the socket first and letting all those messages finish arriving or else you get an error after closing the socket and the subsequent benchmark runs never happen. Probably do-able, but I'm not sure the extra complexity will be worth it. Maybe? If anyone wants to put together a competing implementation that does it that way, please go for it.

[mscdex]

This change is fine with me, I was just curious. LGTM

[Trott]

CI: https://ci.nodejs.org/job/node-test-pull-request/3246/

[mscdex]

Argh, I forgot I already made this change as part of #7311. It would be nice if we could get that to land since it is more comprehensive. Any input on that PR would be great.

[Trott]

Closing in favor of #7311