Reapply "Switch to self hosted mac runner (#12024)" with proper fix (#12278)

* Reapply "Switch to self hosted mac runner (#12024)" with proper fix

This reverts commit 783f9926e3.

* use conditional logic for self-hosted runners

* improve readbility

.github/workflows/build_all.yml

@@ -49,7 +49,6 @@ concurrency:
 
 jobs:
   build_linux:
-    name: Build Linux
     strategy:
       fail-fast: false
     # Don't run scheduled builds on forks:
@@ -60,13 +59,12 @@ jobs:
       build-deps-only: ${{ inputs.build-deps-only || false }}
     secrets: inherit
   build_all:
-    name: Build Non-Linux
     strategy:
       fail-fast: false
       matrix:
         include:
           - os: windows-latest
-          - os: macos-14
+          - os: ${{ vars.SELF_HOSTED && 'orca-macos-arm64' || 'macos-14' }}
             arch: arm64
     # Don't run scheduled builds on forks:
     if: ${{ !cancelled() && (github.event_name != 'schedule' || github.repository == 'OrcaSlicer/OrcaSlicer') }}