ci: use setup-cpp-ubuntu 20 base image for arm build

Author: aminya

.github/workflows/CI.yml

@@ -60,7 +60,8 @@ jobs:
           - os: ubuntu-24.04
             node_arch: arm64
             cpp_arch: amd64_arm64
-            distro: ubuntu20.04
+            distro: none
+            base_image: setup-cpp-ubuntu-gcc:20.04-1.3.0
             native: false
 
           # Musl Alpine Arm
@@ -179,6 +180,7 @@ jobs:
         with:
           arch: aarch64
           distro: ${{ matrix.distro }}
+          base_image: ${{ matrix.base_image }}
           githubToken: ${{ github.token }}
           setup: |
             mkdir -p "${PWD}/build"