Enhance client-side attachment upload validation

As of today, when a attachment is uploaded in Confluence in the attachment's page which exceeds the max size of the attachment set, the file gets uploaded to the server than an error message comes which says "Total upload size is too large, reduce total file size"

This feature request is to put a check at the first place as in when the file is selected which exceeds the max limit size the message or notification would be sent as the file size is bigger than the max limit set.