fix(GlLoadingSpinner): restore gl-spinner-rotate CSS animation

What does this MR do?

When reviewing !4817 (merged) I noticed that in the GlLoadingSpinner story the gl-spinner-rotate CSS animation is ignored in devtools, it doesn't appear to exist in the stylesheet.

note: I'm unsure of the root cause here, I have looked through commits to see what may have removed the gl-spinner-rotate styles and cannot find anything.

question: Did this animation ever exist? It looks like in GitLab .gl-spinner styles are overridden with a custom loading spin animation in app/assets/stylesheets/framework/animations.scss:

@keyframes spin {
  0% { transform: rotate(0deg);}
  100% { transform: rotate(360deg);}
}

/** COMPOSITE ANIMATION CLASSES **/
.gl-spinner {
  @include webkit-prefix(animation-name, spin);
  @include webkit-prefix(animation-iteration-count, infinite);
  @include webkit-prefix(animation-timing-function, linear);
  @include webkit-prefix(animation-duration, 1s);
  transform-origin: 50% 50%;
}

Screenshots or screen recordings

Before	After
CleanShot_2024-11-14_at_10.28.14	CleanShot_2024-11-14_at_10.28.33

Integration merge requests

• GitLab: gitlab!172776 (merged)
• CustomersDot: mr_url
• Status Page: mr_url

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