Fix Jittering (#1334)

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# Description

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Title.
Ported from Fansana/floofstation1#393
Resolves #1277

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# Changelog

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:cl:
- fix: Fixed jittering displacing your character when shaken.

Content.Client/Jittering/JitteringSystem.cs

@@ -45,7 +45,7 @@ private void OnShutdown(EntityUid uid, JitteringComponent jittering, ComponentSh
 
         private void OnAnimationCompleted(EntityUid uid, JitteringComponent jittering, AnimationCompletedEvent args)
         {
-            if(args.Key != _jitterAnimationKey)
+            if (args.Key != _jitterAnimationKey || jittering.LifeStage >= ComponentLifeStage.Stopping)
                 return;
 
             if (TryComp(uid, out AnimationPlayerComponent? animationPlayer)