Frequent projects broken image

Summary

Occasionally an image in frequent projects list is broken and the alt text overflows the bounding box. The images also break on the old navigation, but the fallback is handled better.

This happens when you're not authenticated with SAML SSO.

The same happens for frequent groups.

Steps to reproduce

Possible fixes

The main fix would be to make it so that the broken images still work. However, a quick fix would be to make a more sensible fallback. Either by using a fallback image, or by preventing the alt text from overflowing like in the other examples. Since this component is ultimately a <GlAvatar />, we should probably do the fix there. There's already a CSS rule to set overflow: hidden but since it's also set to display: inline the overflow rule doesn't apply.