[WIP] .github: workflows: Use zephyr-runner v2

This commit updates GitHub Actions workflows to use the zephyr-runner
v2.

Author: stephanosio

.github/workflows/ci.yml

@@ -22,18 +22,19 @@ concurrency:
 jobs:
   build:
     name: Build (${{ matrix.variant.platform }})
-    runs-on: ${{ matrix.variant.builder }}
+    runs-on:
+      group: ${{ matrix.variant.builder }}
 
     strategy:
       fail-fast: true
       matrix:
         variant:
         - platform: linux/amd64
           arch: amd64
-          builder: zephyr-runner-linux-x64-4xlarge
+          builder: zephyr-runner-v2-linux-x64-4xlarge
         - platform: linux/arm64
           arch: arm64
-          builder: zephyr-runner-linux-arm64-4xlarge
+          builder: zephyr-runner-v2-linux-arm64-4xlarge
 
     services:
       registry:
@@ -189,7 +190,8 @@ jobs:
 
   merge:
     name: Merge
-    runs-on: zephyr-runner-linux-x64-4xlarge
+    runs-on:
+      group: zephyr-runner-v2-linux-x64-4xlarge
     needs: build
     if: ${{ github.event_name != 'pull_request' }}