Add support for `number` fields in configurations

[aiwilliams]

https://github.com/JupiterOne/sdk/blob/ddfe39c8242ce791501911ca018d76f95af993f2/packages/integration-sdk-runtime/src/execution/config.ts#L46

The managed runtime environment integration definition and UI support number types for config fields. It is confusing when the integration says a field is a string, and then writes code to handle a string, and yet the runtime will provide a number value.