Relax an eager sled agent assert - #10401

control: job assigned to worker 01M5DJB53HSCCMCTMJJ3FDTPTK [factory aws, i-002938003efa6eb25] (queued for 52 s)
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task: starting task 0: "setup"
task: process exited: duration 3166 ms, exit code 0
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task: starting task 1: "rust-toolchain"
task: process exited: duration 16581 ms, exit code 0
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task: starting task 2: "authentication"
task: process exited: duration 25 ms, exit code 0
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task: starting task 3: "clone repository"
task: process exited: duration 20384 ms, exit code 0
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task: starting task 4: "build"
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| + unset TMPDIR
| + echo 'files in /var/tmp/omicron_tmp (none expected on success):'
| files in /var/tmp/omicron_tmp (none expected on success):
| + find /var/tmp/omicron_tmp -ls
| 134942   32 drwxr-xr-x   2 build    build           2 Oct 20 21:44 /var/tmp/omicron_tmp
| + rmdir /var/tmp/omicron_tmp
task: process exited: duration 1993676 ms, exit code 0
|W| found 6 output files
|W| uploading: /work/cargo-build-analysis.jsonl (1848807 bytes)
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|W| uploading: /work/environment.json (108 bytes)
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|W| uploading: /work/oxidecomputer/omicron/target/nextest/ci/junit.xml (711416 bytes)
|W| uploaded: /work/oxidecomputer/omicron/target/nextest/ci/junit.xml
|W| uploading: /work/oxidecomputer/omicron/target/live-tests-archive.tgz (295520256 bytes)
|W| uploaded: /work/oxidecomputer/omicron/target/live-tests-archive.tgz
|W| uploading: /tmp/nextest-run-archive.zip (3344929 bytes)
|W| uploaded: /tmp/nextest-run-archive.zip
|W| uploading: /tmp/nextest-chrome-trace.json (4526950 bytes)
|W| uploaded: /tmp/nextest-chrome-trace.json