Unused parameter in function ProjectionDescriptor.createPojoJavaImplementation()

The current function is as follows; `inputType` is unused.
```
private static FunctionDescriptor.SerializableFunction createPojoJavaImplementation(
final String[] fieldNames, final BasicDataUnitType inputType) {
// Get the names of the fields to be projected.
if (fieldNames.length != 1) {
return t -> {
throw new IllegalStateException("The projection descriptor currently supports only a single field.");
};
}
final String fieldName = fieldNames[0];
return new PojoImplementation<>(fieldName);
}
```