Boards: try to attach image to card without permission shows wrong error msg

Summary

When viewing a card where you only have commenter permissions and trying to attach an image, the error message indicates the file size is too large (it isn't) instead of stating that you don't have permission.

Steps to reproduce

See screen shot

Expected behavior

Error message should state you do not have permission to attach a file.

Observed behavior (that appears unintentional)