[chore][ci]linux-package-test: remove ubuntu-20.04 GH runner (#6090)

Author: pjanotti

.github/workflows/linux-package-test.yml

@@ -69,7 +69,7 @@ jobs:
             ./bin/*
 
   agent-bundle-linux:
-    runs-on: ${{ fromJSON('["ubuntu-20.04", "otel-arm64"]')[matrix.ARCH == 'arm64'] }}
+    runs-on: ${{ fromJSON('["ubuntu-24.04", "otel-arm64"]')[matrix.ARCH == 'arm64'] }}
     strategy:
       matrix:
         ARCH: ["amd64", "arm64"]
@@ -151,19 +151,14 @@ jobs:
           fi
           distro=$(for d in $dockerfiles; do echo -n "\"$d\","; done)
           arch="\"amd64\", \"arm64\""
-          # amazonlinux-2 requires cgroup v1, only available on version 20.04 that doesn't have an arm runner
-          exclude='{"DISTRO": "amazonlinux-2", "ARCH": "arm64"}'
-          matrix="{\"DISTRO\": [${distro%,}], \"ARCH\": [${arch}], \"exclude\": [${exclude}]}"
+          matrix="{\"DISTRO\": [${distro%,}], \"ARCH\": [${arch}]}"
           echo "$matrix" | jq
           echo "matrix=${matrix}" >> $GITHUB_OUTPUT
     outputs:
       matrix: ${{ steps.get-matrix.outputs.matrix }}
 
   test-package:
-    # Amazon Linux 2 uses cgroup v1
-    # Ubuntu 24.04 uses cgroup v2
-    # Fallback to Ubuntu 20.04 when appropriate
-    runs-on: ubuntu-${{ matrix.DISTRO != 'amazonlinux-2' && '24.04' || '20.04' }}${{ matrix.ARCH == 'arm64' && '-arm' || '' }}
+    runs-on: ubuntu-24.04${{ matrix.ARCH == 'arm64' && '-arm' || '' }}
     timeout-minutes: 30
     needs: [build-package, test-package-matrix]
     strategy: