Removes the CSRF token if the emojis.json is on a CDN

What does this MR do?

As described in https://gitlab.com/gitlab-org/gitlab-ce/issues/58784#note_149269960 there is a problem with the CDN's CORS configuration when accessing the emojis.json this MR will resolve the problem with the CSRF token header by removing it from the request headers.

What are the relevant issue numbers?

Closes #58784 (closed)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated via this MR
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Tested in all supported browsers
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides
• Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.
• Security reports checked/validated by reviewer