Adds Gemini CLI to Github Actions (#2718)

## Pre-launch Checklist

- [x] I read the [Flutter Style Guide] _recently_, and have followed its
advice.
- [x] I signed the [CLA].
- [x] I read the [Contributors Guide].
- [x] I have added sample code updates to the [changelog].
- [x] I updated/added relevant documentation (doc comments with `///`).

.github/workflows/build-android.yml

@@ -0,0 +1,30 @@
+name: Test Android Build
+
+# Declare default permissions as read only.
+permissions: read-all
+
+on:
+  push:
+    branches: [beta]
+  pull_request:
+    branches: [beta]
+  workflow_dispatch:
+
+defaults:
+  run:
+    shell: bash
+  
+jobs:
+  android-build:
+    runs-on: ubuntu-latest
+    if: github.repository == 'flutter/samples'
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
+      - uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165
+        with:
+          distribution: 'zulu'
+          java-version: '17'
+      - uses: subosito/flutter-action@e938fdf56512cc96ef2f93601a5a40bde3801046
+        with:
+          channel: stable
+      - run: ./tool/android_ci_script.sh