chore: add comments to clarify command behaviors

Author: Siqi-Shan

.codebuild/run_android_modelgen_e2e_test.yml

@@ -17,6 +17,9 @@ phases:
       - yes | sudo apt install android-sdk
       - export ANDROID_HOME=/usr/lib/android-sdk
       - yes | sudo apt install sdkmanager
+      # Licenses acceptance is needed for Android project build.
+      # "sdkmanager --licenses" is handled in test beforeAll setup,
+      # and this ensures the project accepts all licenses needed.
 
   build:
     commands:

.codebuild/run_canary_android_modelgen_e2e_test.yml

@@ -15,6 +15,9 @@ phases:
       - yes | sudo apt install android-sdk
       - export ANDROID_HOME=/usr/lib/android-sdk
       - yes | sudo apt install sdkmanager
+      # Licenses acceptance is needed for Android project build.
+      # "sdkmanager --licenses" is handled in test beforeAll setup,
+      # and this ensures the project accepts all licenses needed.
 
   build:
     commands: