arrow

ARROW-8833: [Rust] Implement VALIDATE mode in integration tests

This follows on from https://github.com/apache/arrow/pull/7206 which should be merged first.

This PR partially implements the VALIDATE mode in arrow-json-integration-test.

Closes #7208 from andygrove/ARROW-8833

Authored-by: Andy Grove <andygrove73@gmail.com>
Signed-off-by: Andy Grove <andygrove73@gmail.com>