Add FixedSizeList to pretty_print_batches implementation

[matthewmturner]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.
I am currently working on migrating datafusion sql tests to use the new assert_batches_eq macro to make it easier to view and maintain tests (apache/datafusion#1241). I use pretty_format_batches in order to get the correct output format. I get the below error when trying to use pretty_format_batches on a table with array column.

running 1 test
thread 'query_array' panicked at 'called `Result::unwrap()` on an `Err` value: InvalidArgumentError("Pretty printing not implemented for FixedSizeList(Field { name: \"item\", data_type: Utf8, nullable: true, dict_id: 0, dict_is_ordered: false, metadata: None }, 2) type")', datafusion/tests/sql.rs:3606:46
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
test query_array ... FAILED

Describe the solution you'd like
I would like pretty_format_batches to work on tables with array columns

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.

[brianrackle]

I would like to try to resolve this issue. I am currently reviewing the code and tests to come up with a plan to support the request.