[Spr 12365] use valueOf() method instead of inefficient new Constructor.

In readAnnotationValue() of ClassReader(org.springframework.asm.ClassReader) ,

there are some inefficient new Byte, Character, Integer constructor.

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new Byte((byte) readInt(items[readUnsignedShort(v)])));

-> Byte.valueOf((byte) readInt(items[readUnsignedShort(v)])) );
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This will be better for performance.

ISSUE: spr-12365