Improve emoji autocomplete/typeahead filtering
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When I search for an emoticon with 2 words, like "face palm" I am expecting it to suggest an emoticon when I type "facepalm", but our search only returns a result if I search for "face_palm"
| Expected - SLACK | GITLAB.COM |
|---|---|
|  |  |
//cc @MadLittleMods
## Relevant code
- [`app/assets/javascripts/gfm_auto_complete.js#L180-205`](https://gitlab.com/gitlab-org/gitlab/-/blob/e73e2ef11a18732d1a4c686b1f7ac611be78bcce/app/assets/javascripts/gfm_auto_complete.js#L180-205)
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