[KafkaConnect] Fix RecordConverter for UUID and Fixed Types

[singhpk234]

About the change

The UUID type in the parquet writer expects ByteBuffer rather than UUID otherwise writer fails with :

class java.util.UUID cannot be cast to class [B (java.util.UUID and [B are in module java.base of loader 'bootstrap')

The FixedLength would need byteArray rather than ByteBuffer otherwise one get this error

class java.nio.HeapByteBuffer cannot be cast to class [B (java.nio.HeapByteBuffer and [B are in module java.base of loader 'bootstrap')

Testing

Added new tests

cc @bryanck