Update `MapOpenApiPrimitiveTypeToSimpleType` to handle integers and numbers without a format

[glen-84]

Is your feature request related to a problem? Please describe.

OpenApiTypeMapper.MapOpenApiPrimitiveTypeToSimpleType doesn't handle integers or numbers without a format.

Describe the solution you'd like

Add:

("integer", null, false)
("integer", null, true)
("number", null, false)
("number", null, true)

I'm not sure what types these should default to. Perhaps int + double.

Describe alternatives you've considered

copy/paste/update

Additional context

n/a

[MaggieKimani1]

@glen-84, just to be clear is this request for nullable types only or all data types?

[glen-84]

The 3rd element of the tuple is the nullability, so it would be for both nullable and non-nullable integers and numbers.