Merge pull request opencv#26093 from sturkmen72:related_issue_22090

Update test_tiff.cpp opencv#26093

related opencv#22090

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

Author: sturkmen72

modules/imgcodecs/test/test_tiff.cpp

@@ -1096,7 +1096,6 @@ INSTANTIATE_TEST_CASE_P(AllModes, Imgcodecs_Tiff_Modes, testing::ValuesIn(all_mo
 TEST(Imgcodecs_Tiff_Modes, write_multipage)
 {
     const string root = cvtest::TS::ptr()->get_data_path();
-    const string filename = root + "readwrite/multipage.tif";
     const string page_files[] = {
         "readwrite/multipage_p1.tif",
         "readwrite/multipage_p2.tif",
@@ -1109,7 +1108,7 @@ TEST(Imgcodecs_Tiff_Modes, write_multipage)
     vector<Mat> pages;
     for (size_t i = 0; i < page_count; i++)
     {
-        const Mat page = imread(root + page_files[i]);
+        const Mat page = imread(root + page_files[i], IMREAD_REDUCED_GRAYSCALE_8 + (int)i);
         pages.push_back(page);
     }