- Various tests of the Protobuf format existed already. Most of them
check serialization/deserialization of specific data types, e.g.
arrays, arrays in arrays, enums, maps, columns with default values
etc. There is also an end-to-end test which uses a complex table
that combines aforementioned data types.
- Since "ProtobufList" reuses the data conversion code of "Protobuf"
and only differs slightly in the schema matching logic it should
suffice to extend only the end-to-end test. This avoids testing the
same stuff twice (and the same was done btw. for the ProtobufSingle
format).