If true, the schemas of the tables will be first unified with fields of the same name being merged, according to #GArrowTableConcatenateOptions:promote-nullability, then each table will be promoted to the unified schema before being concatenated.
Otherwise, all tables should have the same schema. Each column in the output table is the result of concatenating the corresponding columns in all input tables.
Builder instance for fluent chaining
Set unifySchemas property.