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https://docs.github.com/en/actions/reference/runners/github-hosted-runners#standard-github-hosted-runners-for-public-repositories

Change-Id: I25307e2a2ff6be737336609d6af326360b7770bc

.github/workflows/Build.yaml

@@ -241,6 +241,8 @@ jobs:
           api-level: ${{ matrix.api-level }}
           arch: x86_64
           disable-animations: true
+          # https://docs.github.com/en/actions/reference/runners/github-hosted-runners#standard-github-hosted-runners-for-public-repositories
+          # Number of core of default public repository github action runner is 4 in all.
           cores: 4
           disk-size: 6000M
           heap-size: 600M