https://trilon.io/blog/announcing-nestjs-8-whats-new#template-literal-types-and-configservice
With the template literal types now available in TypeScript v4.2, we are able to implement a new infer feature that lets us infer the type of a nested custom configuration object's property, even when using dot notation
Since the infer option is non-default and needs to be added each time it is used, we implement it as a default by extending ConfigService in Nest.
See ConfigService of CommonModule
See sample method of SampleController
