Fix border color for following user (#3975)

bad hook deps was causing the wrong presence record to be returned when
switching between following users.

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packages/editor/src/lib/hooks/usePresence.ts

@@ -15,7 +15,7 @@ export function usePresence(userId: string): TLInstancePresence | null {
 		() => {
 			return editor.getCollaborators().find((c) => c.userId === userId)
 		},
-		[editor]
+		[editor, userId]
 	)
 
 	return latestPresence ?? null