Merge pull request #24910 from alexlyulkov:al/android-tests

Modified Java tests to run on Android #24910

To run the tests you need to:

1. Build OpenCV using Android pipeline. For example:
`cmake -DBUILD_TEST=ON -DANDROID=ON -DANDROID_ABI=arm64-v8a -DCMAKE_TOOLCHAIN_FILE=/usr/lib/android-sdk/ndk/25.1.8937393/build/cmake/android.toolchain.cmake -DANDROID_NDK=/usr/lib/android-sdk/ndk/25.1.8937393 -DANDROID_SDK=/usr/lib/android-sdk ../opencv`
`make`
2. Connect Android Phone
3. Run tests:
`cd android_tests`
`./gradlew tests_module:connectedAndroidTest`

Related CI pipeline: https://github.com/opencv/ci-gha-workflow/pull/138

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [x] The feature is well documented and sample code can be built with the project CMake

modules/objdetect/misc/java/test/QRCodeDetectorTest.java

@@ -19,9 +19,14 @@ public class QRCodeDetectorTest extends OpenCVTestCase {
     protected void setUp() throws Exception {
         super.setUp();
 
-        testDataPath = System.getenv(ENV_OPENCV_TEST_DATA_PATH);
-        if (testDataPath == null)
-            throw new Exception(ENV_OPENCV_TEST_DATA_PATH + " has to be defined!");
+        // relys on https://developer.android.com/reference/java/lang/System
+        isTestCaseEnabled = System.getProperties().getProperty("java.vm.name") != "Dalvik";
+
+        if (isTestCaseEnabled) {
+            testDataPath = System.getenv(ENV_OPENCV_TEST_DATA_PATH);
+            if (testDataPath == null)
+                throw new Exception(ENV_OPENCV_TEST_DATA_PATH + " has to be defined!");
+        }
     }
 
     public void testDetectAndDecode() {