Remove unused import (#30544)

Summary:
Remove unused import

## Changelog

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[iOS] [performance] - Remove unused import

Pull Request resolved: #30544

Test Plan: Should build on CI

Reviewed By: lunaleaps

Differential Revision: D30000901

Pulled By: charlesbdudley

fbshipit-source-id: 3d3310917823b7af57564ca1ea397cd32cd0c4d5

Author: jacobp100

React/Base/RCTMultipartStreamReader.m

@@ -7,8 +7,6 @@
 
 #import "RCTMultipartStreamReader.h"
 
-#import <QuartzCore/CAAnimation.h>
-
 #define CRLF @"\r\n"
 
 @implementation RCTMultipartStreamReader {