TableProviderFactory::create should have Optional<DFSchemaRef> parameter

[milenkovicm]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.

datafusion::datasource::datasource::TableProviderFactory::create should have Optional<DFSchemaRef> a parameter to support statements with table DDL e.g: CREATE EXTERNAL TABLE demo_table (c1 integer, c2 integer) STORED AS ... ?

Describe the solution you'd like

add schema: Optional<DFSchemaRef> to method signature

Describe alternatives you've considered

use schema: DFSchemaRef as parameter, which can be empty. I've believe version with Optional make more sense, as it is easier to understand.

Additional context