fix(image_projection_based_fusion): remove unused variable (#8634)

fix: remove unused variable

Signed-off-by: yoshiri <yoshiyoshidetteiu@gmail.com>

Author: YoshiRi

Diff for: perception/autoware_image_projection_based_fusion/src/pointpainting_fusion/node.cpp

@@ -351,7 +351,6 @@ dc   | dc dc dc  dc ||zc|
       // paint current point if it is inside bbox
       int label2d = feature_object.object.classification.front().label;
       if (!isUnknown(label2d) && isInsideBbox(projected_point.x(), projected_point.y(), roi, p_z)) {
-        data = &painted_pointcloud_msg.data[0];
         // cppcheck-suppress invalidPointerCast
         auto p_class = reinterpret_cast<float *>(&output[stride + class_offset]);
         for (const auto & cls : isClassTable_) {