[Backport 6.7.x] fix(rel): fix mise not installing kubectl (#330)

## Description

Fix issue with mise in CI

---

## Checklist



- [x] Update [CHANGELOG.md](https://github.com/sourcegraph/deploy-sourcegraph-k8s/blob/main/CHANGELOG.md)
- [x] Update [K8s Upgrade notes](https://github.com/sourcegraph/sourcegraph/blob/main/doc/admin/updates/kubernetes.md)
- [x] Kustomiz-specific changes
- [x] Update sister repository: [deploy-sourcegraph-helm](https://github.com/sourcegraph/deploy-sourcegraph-helm)
- [x] Update sister repository: [deploy-sourcegraph-docker](https://github.com/sourcegraph/deploy-sourcegraph-docker)
- [x] Verify all images have a valid tag and SHA256 sum

## Test plan

CI
 <br> Backport 00c941d from #329

Author: sourcegraph-release-bot

.tool-versions

@@ -1,6 +1,6 @@
 golang 1.21.5
 yarn 1.22.4
-kubectl 1.25.9
+asdf:kubectl 1.25.9
 fd 7.4.0
 kustomize 4.5.7
 shfmt 3.1.0