Emoji autocomplete kicks in when using reference links

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Summary

When typing a reference link's reference, after the colon (e.g. [link label]:) the emoji pop-up kicks in. The issue is:

1. It gets in the way when trying to type out the actual link uri
2. It frequently sticks around after finishing typing out the link uri (in my browser, at least) and sometimes after the issue is submitted.

Steps to reproduce

1. Type some text
2. Start typing a reference link: (e.g. [link label]: )
3. The emoji pop-up kicks in

What is the current bug behavior?

The emoji pop-up kicks in when typing out a reference link, after the colon, and even sticking around after the subsequent space character.

What is the expected correct behavior?

No emoji popup when typing a colon which is not a deliberate start to an emoji, particularly when the colon is part of a reference link.

Results of GitLab environment info

This happens on whichever version of gitlab I'm reporting this on right now.