Issue Summary

When I add the card attachment as Slack workspace link, Trello is advertising the option to "Connect your Slack account"

Steps to Reproduce

1. Open a card 
2. Click on attachment 
3. Copy and paste the Slack link 
4. Trello prompts users to Connect slack account 

Expected Results

Users should not get the advertisment to connect the slack account instead there should be only the link when we hover it. 

Actual Results

The user's preferences are not being saved for those attachments. 

Workaround

Currently, there is no known workaround for this behavior. A workaround will be added here when available.