fix(runtime): Deno.memoryUsage().rss should return correct value

[dsherret]

Closes #16581

[bartlomieju]

@kangelopoulos hopefully this fixes your problem, here's example numbers I get on mac:

$ cargo run
Deno 1.29.1
exit using ctrl+d, ctrl+c, or close()
REPL is running with all permissions allowed.
To specify permissions, run `deno repl` with allow flags.
> Deno.memoryUsage()
{ rss: 203079680, heapTotal: 3964928, heapUsed: 3556760, external: 225 }
>

[dsherret]

Verified this returns back about the same number as when I do:

> wmic process where processid=<pid goes here> get WorkingSetSize

[bartlomieju]

Verified the same on macos

[magurotuna]

on Ubuntu 22.04.1

$ cargo run
    Finished dev [unoptimized + debuginfo] target(s) in 0.23s
     Running `target/debug/deno`
Deno 1.29.1
exit using ctrl+d, ctrl+c, or close()
REPL is running with all permissions allowed.
To specify permissions, run `deno repl` with allow flags.
> Deno.memoryUsage()
{ rss: 217903104, heapTotal: 3915776, heapUsed: 3585416, external: 225 }

Verified the RSS value roughly matches what ps aux | grep deno shows.

---

For comparison, here's the result of when running on Deno 1.29.1 (released one):

$ deno
Deno 1.29.1
exit using ctrl+d, ctrl+c, or close()
REPL is running with all permissions allowed.
To specify permissions, run `deno repl` with allow flags.
> Deno.memoryUsage()
{ rss: 3899392, heapTotal: 3907584, heapUsed: 3576700, external: 225 }

[bartlomieju]

Thanks for checking @magurotuna!

[bartlomieju]

LGTM