Merge #6561: ci: use arm runners for guix

04a322c ci: guix use arm (pasta)

Pull request description:

  ## Issue being fixed or feature implemented
  (At least currently, in public beta, maybe they'll be worse when more congested) Arm runners appear about 20% faster.

  ## What was done?
  Use arm64 runners for guix instead of x86.

  ## How Has This Been Tested?
  Udjin's patch recently: https://github.com/UdjinM6/dash/actions/runs/13187795136
  vs this commit: (with his as well)
  https://github.com/PastaPastaPasta/dash/actions/runs/13188732140

  ## Breaking Changes

  ## Checklist:
  - [ ] I have performed a self-review of my own code
  - [ ] I have commented my code, particularly in hard-to-understand areas
  - [ ] I have added or updated relevant unit/integration/functional/e2e tests
  - [ ] I have made corresponding changes to the documentation
  - [x] I have assigned this pull request to a milestone _(for repository code-owners and collaborators only)_

ACKs for top commit:
  UdjinM6:
    ACK 04a322c
  kwvg:
    utACK 04a322c

Tree-SHA512: 4494692aae79a58b62e36f188f61c781f75fd69e30cf195d72f8536353e75b30ddb3ed2f67765a7abf6228104fb044af37f30453195a2d114cad96fc4c445177

.github/workflows/guix-build.yml

@@ -11,7 +11,7 @@ on:
 
 jobs:
   build-image:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04-arm
     outputs:
       image-tag: ${{ steps.prepare.outputs.image-tag }}
       repo-name: ${{ steps.prepare.outputs.repo-name }}
@@ -64,7 +64,7 @@ jobs:
   build:
     needs: build-image
     # runs-on: [ "self-hosted", "linux", "x64", "ubuntu-core" ]
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04-arm
 #    if: ${{ contains(github.event.pull_request.labels.*.name, 'guix-build') }}
     strategy:
       matrix: