ci: Lint GitHub Actions workflows with actionlint (#34729)

Added [rhysd/actionlint](https://github.com/rhysd/actionlint/) a static
checker for GitHub Actions workflow files.
Install locally with `brew install actionlint` the run with
`actionlint`.

Inspired by: https://github.com/zed-industries/zed/pull/34704 which
yielded this observation:

> In github actions: 
> 1. strings are truthy
> 2. `${{ }}` will become a string if it doesn't wrap the whole value.
>
> So `if: false && true` becomes `false`
> and `if: ${{ false && true }}` becomes `false`
> but `if: false && ${{ true }}` becomes `"false && true"` which
evaluates true
> The reason you sometimes need `${{ }}` is because YAML doesn't like
`!`
> so `if: !false` is invalid yaml
> and `if: ${{ !false }}` works just fine.

Changes:
- Add `actionlint` job
- Refactor `job_spec` job to be more readable
- Fix all `actionlint` and `shellcheck` errors in Actions workflows (62
in all)
- Add `self-mini-macos` and `self-32vcpu-windows-2022` labels to
self-hosted runners. Not strictly related, but useful if you need to
take a runner out of the rotation (since `macOS`, `self-hosted`, and
`ARM64` are auto-set and cannot be added/removed).
- Change ci.yml macos_relase to target `self-mini-macos` instead of
`bundle` which was previously deprecated.

This would've caught the error fixed in
https://github.com/zed-industries/zed/pull/34704. Here's what that [job
failure](https://github.com/zed-industries/zed/actions/runs/16376993944/job/46279281842?pr=34729)
would've looked like.

Release Notes:

- N/A

.github/workflows/deploy_collab.yml

@@ -79,12 +79,12 @@ jobs:
       - name: Build docker image
         run: |
           docker build -f Dockerfile-collab \
-            --build-arg GITHUB_SHA=$GITHUB_SHA \
-            --tag registry.digitalocean.com/zed/collab:$GITHUB_SHA \
+            --build-arg "GITHUB_SHA=$GITHUB_SHA" \
+            --tag "registry.digitalocean.com/zed/collab:$GITHUB_SHA" \
             .
 
       - name: Publish docker image
-        run: docker push registry.digitalocean.com/zed/collab:${GITHUB_SHA}
+        run: docker push "registry.digitalocean.com/zed/collab:${GITHUB_SHA}"
 
       - name: Prune Docker system
         run: docker system prune  --filter 'until=72h' -f
@@ -131,7 +131,8 @@ jobs:
           source script/lib/deploy-helpers.sh
           export_vars_for_environment $ZED_KUBE_NAMESPACE
 
-          export ZED_DO_CERTIFICATE_ID=$(doctl compute certificate list --format ID --no-header)
+          ZED_DO_CERTIFICATE_ID="$(doctl compute certificate list --format ID --no-header)"
+          export ZED_DO_CERTIFICATE_ID
           export ZED_IMAGE_ID="registry.digitalocean.com/zed/collab:${GITHUB_SHA}"
 
           export ZED_SERVICE_NAME=collab