Merge pull request #24028 from VadimLevin:dev/vlevin/fix-flann-python-bindings

Fix FLANN python bindings #24028

As a side-effect this patch improves reporting errors by FLANN `get_param`.

resolves #21642

### 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
- [x] There is a reference to the original bug report and related work
- [x] 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/flann/misc/python/test/test_flann_based_matcher.py

@@ -0,0 +1,30 @@
+#!/usr/bin/env python
+# Python 2/3 compatibility
+from __future__ import print_function
+
+import cv2
+import numpy as np
+
+from tests_common import NewOpenCVTests
+
+
+class FlannBasedMatcher(NewOpenCVTests):
+    def test_all_parameters_can_be_passed(self):
+        img1 = self.get_sample("samples/data/right01.jpg")
+        img2 = self.get_sample("samples/data/right02.jpg")
+
+        orb = cv2.ORB.create()
+
+        kp1, des1 = orb.detectAndCompute(img1, None)
+        kp2, des2 = orb.detectAndCompute(img2, None)
+        FLANN_INDEX_KDTREE = 1
+        index_param = dict(algorithm=FLANN_INDEX_KDTREE, trees=4)
+        search_param = dict(checks=32, sorted=True, eps=0.5,
+                            explore_all_trees=False)
+        matcher = cv2.FlannBasedMatcher(index_param, search_param)
+        matches = matcher.knnMatch(np.float32(des1), np.float32(des2), k=2)
+        self.assertGreater(len(matches), 0)
+
+
+if __name__ == '__main__':
+    NewOpenCVTests.bootstrap()