Well, I would like to give an update on this.
I also haven't uploaded my IELTS result on the system as it was not among the required documents. I thought the system obtains the results from the test agency itself through the IELTS number I provided. However, I was horrified when I read your comment stating it should have been uploaded, and called the IRCC helpline to make sure it hasn't jeopardized my application. The agent first told me that if it is not among the required documents list, I don't have to upload it, and suggested to confirm this with his superior. After an additional 5-minute hold, he confirmed that the IELTS result number would be sufficient since the system automatically acquires the results with that number and I don't need to provide the scanned copy.
If this is the case, I believe, it would be wise to relax and try not to increase the IRCC's workload by submitting additional documents that are not required. The more their workload is, the longer will the processing times be. Just an idea.