Merge pull request #27338 from omahs:patch-1

Fix typos #27338

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

modules/ml/src/gbt.cpp

@@ -256,7 +256,7 @@ CvGBTrees::train( const CvMat* _train_data, int _tflag,
     // inside gbt learning process only regression decision trees are built
     data->is_classifier = false;
 
-    // preproccessing sample indices
+    // preprocessing sample indices
     if (_sample_idx)
     {
         int sample_idx_len = get_len(_sample_idx);