docs: Homepage link typo for flame_spine (#3277)

The link to the homepage for the flame_spine package has a typo in it.
This PR fixes the link.

packages/flame_spine/pubspec.yaml

@@ -1,7 +1,7 @@
 name: flame_spine
 description: Spine support for the Flame game engine. This uses the spine_flutter package and provides wrappers and components to be used inside Flame.
 version: 0.2.1
-homepage: https://github.com/flame-engine/flame/tree/main/packages/flame_sprine
+homepage: https://github.com/flame-engine/flame/tree/main/packages/flame_spine
 funding:
   - https://opencollective.com/blue-fire
   - https://github.com/sponsors/bluefireteam