Merge pull request #26850 from shyama7004:update-headers

Update includes in filter.hpp #26850

Fixes :
```
identifier "Mat" is undefinedC/C++(20)
namespace "std" has no member "vector"C/C++(135)
```

### 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
- [ ] 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/imgproc/src/filter.hpp

@@ -43,6 +43,9 @@
 #ifndef OPENCV_IMGPROC_FILTER_HPP
 #define OPENCV_IMGPROC_FILTER_HPP
 
+#include <opencv2/core.hpp>
+#include <vector>
+
 namespace cv
 {
 #ifdef HAVE_OPENCL