Fixes todos not rendering custom emoji
What does this MR do and why?
Fixes a bug where the fallback src data attribute for custom emoji gets filtered out on todos.
MR acceptance checklist
Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.
Screenshots or screen recordings
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How to set up and validate locally
- Create a custom emoji (http://gdk.test:3000/groups/gitlab-org/-/custom_emoji/new)
- Create a new note on a merge request/issue that mentions the current user with a custom emoji
- Visit todos