FlightSQL: Add helpers to create CommandGetXdbcTypeInfo responses (XdbcInfoValue and builders)

[alamb]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.
FlightSQL has several metadata APIs for a server to report its capabilities to the client. One such API is the CommandGetXdbcTypeInfo message that requires creating a DenseUnion (which is somewhat inconvenient in the Rust API):

https://github.com/apache/arrow/blob/f9324b79bf4fc1ec7e97b32e3cce16e75ef0f5e3/format/FlightSql.proto#L1058-L1116

@roeap noted in #4250 (comment) that some of the existing work we did in IOx could be used by other rust projects implementing FlightSQL:

https://github.com/influxdata/influxdb_iox/blob/31b881376057bf7e50381519c4f5c9e15c1aee33/flightsql/src/xdbc_type_info/mod.rs

Describe the solution you'd like

1. Create a builder for XdbcTypeInfo responses in the arrow-rs flightsql implementation: https://github.com/apache/arrow-rs/tree/master/arrow-flight/src/sql
2. Create code that will convert these rust structs to the corresponding Arrow arrays
3. Add tests and docstrings showing how to use this builder
4. Update the example server

   arrow-rs/arrow-flight/examples/flight_sql_server.rs

   Lines 318 to 326 in e2b9b1a

   	async fn get_flight_info_xdbc_type_info(
   	&self,
   	_query: CommandGetXdbcTypeInfo,
   	_request: Request<FlightDescriptor>,
   	) -> Result<Response<FlightInfo>, Status> {
   	Err(Status::unimplemented(
   	"get_flight_info_xdbc_type_info not implemented",
   	))
   	}

   to use this XdbcTypeInfoBuilder

I suggest following the model / copying code from IOx's [XdbcTypeInfo]:

https://github.com/influxdata/influxdb_iox/blob/31b881376057bf7e50381519c4f5c9e15c1aee33/flightsql/src/xdbc_type_info/value.rs#L146C16-L171

Describe alternatives you've considered

Additional context
Marking this as a good first issue as it is well specified and the implementation already exists for inspiration

[alamb]

label_issue.py automatically added labels {'arrow'} from #4250