AK: Remove unused include from MemoryStream

Author: https://github.com/BenWiederhake
Commit: https://github.com/LadybirdBrowser/ladybird/commit/5459f882e97
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/7986
Reviewed-by: https://github.com/AtkinsSJ ✅
Reviewed-by: https://github.com/gmta ✅

AK/MemoryStream.h

@@ -8,7 +8,6 @@
 #pragma once
 
 #include <AK/Error.h>
-#include <AK/OwnPtr.h>
 #include <AK/Stream.h>
 #include <AK/Vector.h>
 

Libraries/LibCompress/PackBitsDecoder.cpp

@@ -6,6 +6,7 @@
 
 #include "PackBitsDecoder.h"
 #include <AK/MemoryStream.h>
+#include <AK/NonnullOwnPtr.h>
 
 namespace Compress::PackBits {
 

Tests/LibDiff/TestDiff.cpp

@@ -5,6 +5,7 @@
  */
 
 #include <AK/MemoryStream.h>
+#include <AK/NonnullOwnPtr.h>
 #include <LibDiff/Format.h>
 #include <LibDiff/Generator.h>
 #include <LibTest/TestCase.h>