Eaxmples: Android: Fix build failed issue. (#7832)

set android:exported to true (IntentFilter)

Signed-off-by: Sunrisepeak <speakshen@163.com>

examples/example_android_opengl3/android/app/src/main/AndroidManifest.xml

@@ -11,7 +11,7 @@
             android:name="imgui.example.android.MainActivity"
             android:theme="@android:style/Theme.NoTitleBar.Fullscreen"
             android:configChanges="orientation|keyboardHidden|screenSize"
-            android:exported="false">
+            android:exported="true">
             <meta-data android:name="android.app.lib_name"
                 android:value="ImGuiExample" />