OpenApiPrimitive Write for OpenApiString does not take into account IsExplicit

[WillGunn]

OpenAPI.NET/src/Microsoft.OpenApi/Any/OpenApiPrimitive.cs

Lines 71 to 74 in 8851cf3

	case PrimitiveType.String:
	var stringValue = (OpenApiString)(IOpenApiPrimitive)this;
	writer.WriteValue(stringValue.Value);
	break;

Currently there is no way to write a raw string value without json encoding it as the writer does not take into account the IsExplicit value stored in OpenApiString. This feels like a bug, if so an easy fix would be to check if OpenApiString.IsExplicit() is true then call WriteRaw instead of WriteValue. If this would cause backwards compatibility issues, I suggest adding another parameter to OpenApiString that allows its contents to be called with WriteRaw instead of WriteValue.

[WillGunn]

Relevant issue that led to this,
mattfrear/Swashbuckle.AspNetCore.Filters#162