update go toolchain to 1.26 - #47

control: job assigned to worker 01KQD8B5VWTYF2XB7N7EXP7KFM [factory aws, i-02aa5da878e78b810] (queued for 28 s)
...
task: starting task 0: "setup"
task: process exited: duration 18615 ms, exit code 0
...
task: starting task 1: "authentication"
task: process exited: duration 5 ms, exit code 0
...
task: starting task 2: "clone repository"
task: process exited: duration 39442 ms, exit code 0
...
task: starting task 3: "build"
...
| + artifact_name=build
| + curl -sSfL --netrc -o build.zip https://api.github.com/repos/oxidecomputer/cockroach/act [...]
| + for artifact_id in $(jq -r '.id' <<<"$artifacts")
| ++ jq -r --argjson id 6715047961 'select(.id == $id) | .name'
| + artifact_name=arm64
| + curl -sSfL --netrc -o arm64.zip https://api.github.com/repos/oxidecomputer/cockroach/act [...]
| + for artifact_id in $(jq -r '.id' <<<"$artifacts")
| ++ jq -r --argjson id 6715012218 'select(.id == $id) | .name'
| + artifact_name=amd64
| + curl -sSfL --netrc -o amd64.zip https://api.github.com/repos/oxidecomputer/cockroach/act [...]
| + unzip build.zip
| Archive:  build.zip
|  extracting: cockroach.tgz.sha256
|  extracting: cockroach.tgz
task: process exited: duration 587306 ms, exit code 0
|W| found 2 output files
|W| uploading: /work/oxidecomputer/cockroach/cockroach.tgz (195200228 bytes)
|W| uploaded: /work/oxidecomputer/cockroach/cockroach.tgz
|W| uploading: /work/oxidecomputer/cockroach/cockroach.tgz.sha256 (65 bytes)
|W| uploaded: /work/oxidecomputer/cockroach/cockroach.tgz.sha256