Make disk location required in sled-agent inventory and Nexus - #11628

control: job assigned to worker 01M6EWRFGS03HWKJAJ70JDGHZP [factory aws, i-0b5290a54fefcaff0] (queued for 54 s)
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task: starting task 0: "setup"
task: process exited: duration 4100 ms, exit code 0
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task: starting task 1: "rust-toolchain"
task: process exited: duration 16950 ms, exit code 0
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task: starting task 2: "authentication"
task: process exited: duration 42 ms, exit code 0
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task: starting task 3: "clone repository"
task: process exited: duration 21626 ms, exit code 0
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task: starting task 4: "build"
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| info: running `cargo check --bins` on zone-setup (372/372)
| warning: profile package spec `blake2b_simd` in profile `dev` did not match any packages
| 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 1.54s
| 
| real    12:25.716981185
| user    19:23.630781405
| sys      4:09.438488763
| trap        0.335250717
| tflt        0.597258336
| dflt        0.928122794
| kflt        0.003986624
| lock  1:00:39.783734119
| slp   1:32:05.147426772
| lat        38.841576353
| stop     3:25.566119271
task: process exited: duration 889313 ms, exit code 0
|W| found 0 output files