Add the sush proxy to the switch zone - #11253

control: job assigned to worker 01M28YJW0T6JHYG94RJRHESAAQ [factory aws, i-0e9fc8a3bbc46ef1b] (queued for 44 s)
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task: starting task 0: "setup"
task: process exited: duration 4096 ms, exit code 0
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task: starting task 1: "rust-toolchain"
task: process exited: duration 18836 ms, exit code 0
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task: starting task 2: "authentication"
task: process exited: duration 19 ms, exit code 0
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task: starting task 3: "clone repository"
task: process exited: duration 23359 ms, exit code 0
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task: starting task 4: "build"
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| warning: profile package spec `rust-argon2` in profile `dev` did not match any packages
|     Checking uzers v0.12.2
|     Checking zone-setup v0.1.0 (/work/oxidecomputer/omicron/zone-setup)
|     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.78s
| warning: the following packages contain code that will be rejected by a future version of  [...]
| note: to see what the problems were, use the option `--future-incompat-report`, or run `ca [...]
| 
| real    14:41.156578739
| user    21:51.666486552
| sys      4:36.884023772
| trap        0.332061850
| tflt        0.526936234
| dflt        0.846577793
| kflt        0.005115764
| lock  1:31:43.234570230
| slp   1:44:33.803518974
| lat        59.004015295
| stop     4:25.872961322
task: process exited: duration 1024876 ms, exit code 0
|W| found 0 output files