bump jobserver dependency

[the8472]

the newest jobserver version should slightly reduce context switches
in highly parallel build environments on linux kernels >= 5.6

[rust-highfive]

r? @Mark-Simulacrum

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[Mark-Simulacrum]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

@rustbot label: +S-waiting-on-perf

[bors]

⌛ Trying commit 7f45cdb with merge 25c7c6d...

[Mark-Simulacrum]

The perf server currently has a 4.15 kernel, so this won't obviously see results there, but hopefully also does not show a regression; the perf server should have no real parallelism competition (as the measurements are either done in -j1 or with a single rustc).

[bors]

☀️ Try build successful - checks-actions
Build commit: 25c7c6d (25c7c6d87b2b90db60f22ee377076fb16556f5ee)

[rust-timer]

Queued 25c7c6d with parent b849326, future comparison URL.

[rust-timer]

Finished benchmarking try commit (25c7c6d): comparison url.

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. Please note that if the perf results are neutral, you should likely undo the rollup=never given below by specifying rollup- to bors.

Importantly, though, if the results of this run are non-neutral do not roll this PR up -- it will mask other regressions or improvements in the roll up.

@bors rollup=never
@rustbot label: +S-waiting-on-review -S-waiting-on-perf

[Mark-Simulacrum]

Looks entirely neutral, as expected; once this lands we may try to get some local testing on a larger machine (I know @joshtriplett had access at one point), but ultimately it's likely not necessary. @bors r+

[bors]

📌 Commit 7f45cdb has been approved by Mark-Simulacrum

[bors]

⌛ Testing commit 7f45cdb with merge c757729...

[bors]

☀️ Test successful - checks-actions
Approved by: Mark-Simulacrum
Pushing c757729 to master...