Accessibility fix: avoid animation rotation

- Disables rotating spinner animation when users have reduced motion preference enabled in their OS/browser settings
- This prevents discomfort for users with motion-triggered vestibular disorders

Author: kaushalnavneet

packages/components/src/components/Spinner/_Spinner.scss

@@ -1,5 +1,5 @@
 /*
-Copyright 2019-2020 The Tekton Authors
+Copyright 2019-2026 The Tekton Authors
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
@@ -26,3 +26,9 @@ limitations under the License.
     transform: rotate(360deg) scaleX(-1);
   }
 }
+
+@media (prefers-reduced-motion: reduce) {
+  .tkn--spinner {
+    animation: none;
+  }
+}