build: update modules descriptions

modules/highgui/CMakeLists.txt

-set(the_description "High-level GUI and Media I/O")
+set(the_description "High-level GUI")
 ocv_add_module(highgui opencv_imgproc opencv_imgcodecs OPTIONAL opencv_videoio WRAP python)
 
 # ----------------------------------------------------------------------------

modules/imgcodecs/CMakeLists.txt

-set(the_description "Image codecs")
+set(the_description "Image I/O")
 ocv_add_module(imgcodecs opencv_imgproc WRAP java python)
 
 # ----------------------------------------------------------------------------

modules/shape/CMakeLists.txt

-set(the_description "Shape descriptors and matchers.")
+set(the_description "Shape descriptors and matchers")
 ocv_define_module(shape opencv_core opencv_imgproc opencv_video WRAP python)

modules/world/CMakeLists.txt

-set(the_description "All the selected OpenCV modules in a single binary")
+set(the_description "All OpenCV modules")
 set(OPENCV_MODULE_IS_PART_OF_WORLD FALSE)
 set(BUILD_opencv_world_INIT OFF)