[ci] Switch to gh workers for arm64 (#3090)

.github/workflows/build-linux-binaries.yml

@@ -71,7 +71,7 @@ jobs:
           rm -rf /tmp/avalanchego
 
   build-arm64-binaries-tarball:
-    runs-on: [self-hosted, linux, ARM64, focal]
+    runs-on: custom-arm64-focal
 
     steps:
       - uses: actions/checkout@v4

.github/workflows/build-ubuntu-arm64-release.yml

@@ -12,7 +12,7 @@ on:
 
 jobs:
   build-jammy-arm64-package:
-    runs-on: [self-hosted, linux, ARM64, jammy]
+    runs-on: custom-arm64-jammy
 
     steps:
       - uses: actions/checkout@v4
@@ -69,7 +69,7 @@ jobs:
           rm -rf /tmp/avalanchego
 
   build-focal-arm64-package:
-    runs-on: [self-hosted, linux, ARM64, focal]
+    runs-on: custom-arm64-focal
 
     steps:
       - uses: actions/checkout@v4

.github/workflows/ci.yml

@@ -28,14 +28,20 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [macos-12, ubuntu-20.04, ubuntu-22.04, windows-2022, [self-hosted, linux, ARM64, focal], [self-hosted, linux, ARM64, jammy]]
+        os: [macos-12, ubuntu-20.04, ubuntu-22.04, windows-2022, custom-arm64-focal, custom-arm64-jammy]
     steps:
       - uses: actions/checkout@v4
       - uses: ./.github/actions/setup-go-for-project-v3
       - name: Set timeout on Windows # Windows UT run slower and need a longer timeout
         shell: bash
         if: matrix.os == 'windows-2022'
         run: echo "TIMEOUT=240s" >> $GITHUB_ENV
+      - name: Install build dependencies not available by default on custom-arm64-focal runners
+        shell: bash
+        if: matrix.os == 'custom-arm64-focal'
+        run: |
+          sudo apt update
+          sudo apt -y install build-essential
       - name: build_test
         shell: bash
         run: ./scripts/build_test.sh