Add NDK in CI

.github/workflows/android.yml

@@ -8,7 +8,7 @@ on:
 
 jobs:
   build:
-
+    name: Build
     runs-on: ubuntu-latest
 
     steps:
@@ -29,13 +29,6 @@ jobs:
       run: |
         go install golang.org/x/mobile/cmd/gomobile@latest
         ~/go/bin/gomobile init
-      
-    - name: Build Yggdrasil
-      run: |
-        mkdir app/libs
-        cd yggdrasil-go
-        PATH=$PATH:~/go/bin/ ./contrib/mobile/build -a
-        cp {yggdrasil.aar,yggdrasil-sources.aar} ../app/libs
     
     - name: Set up JDK 11
       uses: actions/setup-java@v3
@@ -43,6 +36,22 @@ jobs:
         java-version: '11'
         distribution: 'temurin'
         cache: gradle
+        
+    - name: Install NDK
+      uses: nttld/setup-ndk@v1
+      id: setup-ndk
+      with:
+        ndk-version: r21e
+        add-to-path: false
+      
+    - name: Build Yggdrasil
+      run: |
+        mkdir app/libs
+        cd yggdrasil-go
+        PATH=$PATH:~/go/bin/ ./contrib/mobile/build -a
+        cp {yggdrasil.aar,yggdrasil-sources.aar} ../app/libs
+      env:
+        ANDROID_NDK_HOME: ${{ steps.setup-ndk.outputs.ndk-path }}
 
     - name: Gradle build
       run: |