Merge pull request #24597 from MaximSmolskiy:fix-bug-in-ChessBoardDetector-findQuadNeighbors

Fix bug in ChessBoardDetector::findQuadNeighbors #24597

### Pull Request Readiness Checklist

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- [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.
- [ ] The feature is well documented and sample code can be built with the project CMake

modules/calib3d/src/calibinit.cpp

@@ -1630,7 +1630,7 @@ void ChessBoardDetector::findQuadNeighbors()
                     {
                         // check edge lengths, make sure they're compatible
                         // edges that are different by more than 1:4 are rejected
-                        float ediff = cur_quad.edge_len - q_k.edge_len;
+                        const float ediff = fabs(cur_quad.edge_len - q_k.edge_len);
                         if (ediff > 32*cur_quad.edge_len ||
                             ediff > 32*q_k.edge_len)
                         {