[ci] Enable building tests for android (#811)

Even if we don't run them, it is useful to know whether they compile or
not.

.github/workflows/build.yml

@@ -285,14 +285,26 @@ jobs:
     - name: "SCM Checkout"
       uses: actions/checkout@v4
 
+    - name: Install haxe
+      uses: krdlab/setup-haxe@v2
+      with:
+        haxe-version: latest
+
+    - name: "Configure: Haxelib"
+      run: |
+        set -eux
+
+        haxelib setup ~/haxelib
+        haxelib install hashlink
+        haxelib list
+
     - name: "Build: Hashlink"
       run: |
         set -ex
         mkdir build
         cd build
         cmake .. -G Ninja --toolchain $ANDROID_NDK_HOME/build/cmake/android.toolchain.cmake \
-          -DANDROID_PLATFORM=24 -DANDROID_ABI=arm64-v8a -DBUILD_SHARED_LIBS=OFF \
-          -DBUILD_TESTING=OFF -DWITH_VM=OFF
+          -DANDROID_PLATFORM=24 -DANDROID_ABI=arm64-v8a -DBUILD_SHARED_LIBS=OFF -DWITH_VM=OFF
         cmake --build .
 
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