Add vsock phd smoketest - #1086

control: job assigned to worker 01KMK4PBH4NMFSP4X9RYJP5YZV [factory aws, i-0dcc05fa5db9b32d8] (queued for 55 s)
...
task: starting task 0: "setup"
task: process exited: duration 4144 ms, exit code 0
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task: starting task 1: "rust-toolchain"
task: process exited: duration 18238 ms, exit code 0
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task: starting task 2: "authentication"
task: process exited: duration 16 ms, exit code 0
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task: starting task 3: "clone repository"
task: process exited: duration 1901 ms, exit code 0
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task: starting task 4: "build"
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| + pfexec mkdir -p /out
| + pfexec chown 12345 /out
| + cp .github/buildomat/phd-run-with-args.sh /out/phd-run-with-args.sh
| + mv target/debug/propolis-server-debug.tar.gz /out/propolis-server-debug.tar.gz
| + mv target/debug/phd-runner.tar.gz /out/phd-runner.tar.gz
| + cd /out
| + digest -a sha256 propolis-server-debug.tar.gz
| + digest -a sha256 phd-runner.tar.gz
task: process exited: duration 346077 ms, exit code 0
|W| found 5 output files
|W| uploading: /out/phd-run-with-args.sh (2573 bytes)
|W| uploaded: /out/phd-run-with-args.sh
|W| uploading: /out/phd-runner.sha256.txt (65 bytes)
|W| uploaded: /out/phd-runner.sha256.txt
|W| uploading: /out/phd-runner.tar.gz (110586099 bytes)
|W| uploaded: /out/phd-runner.tar.gz
|W| uploading: /out/propolis-server-debug.sha256.txt (65 bytes)
|W| uploaded: /out/propolis-server-debug.sha256.txt
|W| uploading: /out/propolis-server-debug.tar.gz (185480387 bytes)
|W| uploaded: /out/propolis-server-debug.tar.gz