Accessibility: Markdown emoji links are not accessible

Summary

When using emojis in links, the title attribute in the <gl-emoji> incorrectly overrides the parent <a> title attribute. This makes links very confusing for Screenreader users, in that it will not announce what the link means properly.

It also poses a problem for all users, including those with cognitive disabilities, that don't understand what the emoji is meant to depict.

Steps to reproduce

View this snippet and hover over the emojis to view the tooltip. Or, use a Screeenreader to focus the links. https://gitlab.com/snippets/1785217

Example Project

https://gitlab.com/snippets/1785217

What is the current bug behavior?

The title of the <gl-emoji> component overrides the <a> title/label.

What is the expected correct behavior?

The <a> title/label is announced to screenreaders, and shown on hover.

Output of checks

This bug happens on GitLab.com

Possible fixes

This was encountered when using the popular all-contributors tool on our GitLab EE instance. GitHub does not have the same problem, as they do not use a title attribute on their <g-emoji> component. Not using a title attribute on the <gl-emoji> tag should fix the accessibility problem.

Rendered HTML on GitLab:

<a href="https://gitlab.com/foo/bar/commits/master" title="Code">
  <gl-emoji title="personal computer" data-name="computer" data-unicode-version="6.0">💻</gl-emoji>
</a>

Rendered HTML on GitHub:

<a href="https://github.com/jfmengels/all-contributors-cli/commits?author=jfmengels" title="Code"> 
  <g-emoji class="g-emoji" alias="computer" fallback-src="https://assets-cdn.github.com/images/icons/emoji/unicode/1f4bb.png">💻</g-emoji>
</a>