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GH-38246: [JAVA] added new getTransferPair() function that takes in a Field type for Complex Type Vectors (#38261)



### Rationale for this change

Additionally, a new function **getTransferPair(Field, Allocator)** is introduced so that a new Field method is not constructed each time getTransferPair is called on the Vector.
Added Field.setChildren() method and made **children** not final - for updating **field** object inside complex vector(it possible that Field will be without children on creation) - optimisation for keeping using already existing Field object.

### What changes are included in this PR?

- `getTransferPair` method for ComplexType Vectors and for BaseVariableWidthVector's

- added `Field.setChildren()` method and made **children** not final - for updating **field** object inside complex vector(it possible that Field will be without children on creation) - optimisation for keeping using already existing Field object.

### Are these changes tested?

Yes, some tests have been added to verify these changes.
### Are there any user-facing changes?

Yes.

**This PR includes breaking changes to public APIs.**

* Closes: #38246

Lead-authored-by: Ivan Chesnov <ivan.chesnov@dremio.com>
Co-authored-by: Ivan Chesnov <xxxlaykxxx@gmail.com>
Signed-off-by: David Li <li.davidm96@gmail.com>