PR: Fix #3720

[u7305790]

Add methods corresponding to the requirements in #3720 and tests

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[u7305790]

PR: Fix #3720

Update:
indexOf(byte[] array, byte target, int fromIndex) [Byte.java]
indexOf(byte[] array, byte[] target, int fromIndex) [Byte.java]
lastIndexOf(byte[] array, byte target, int fromIndex) [Byte.java]
lastIndexOf(byte[] array, byte[] target, int fromIndex) [Byte.java]

These 4 methods are written strictly according to the requirements of the issue #3720.

Unit Tests written:
testIndexOf_arrayTarget_fromIndex() [ByteTest.java]
testIndexOf_fromIndex() [ByteTest.java]
testLastIndexOf_fromIndex() [ByteTest.java]

These tests try to cover a case coverage as comprehensively as possible.

I think the requirements of this issue have been met. If there are extra requirements or bugs exists, please just comment here.

Thanks for reviewing it!