feat(oas): identify required fields in responses - admin (#3278)

## Scope

Admin routes

## What

Add OAS `required` to response schemas.

## Why

Code generator can use the `required` property of a schema to mark fields as optional or not when generating TS types.

## Test

* Run `yarn build`
* Run `yarn openapi:generate`
* Run `yarn redocly preview-docs docs/api/admin/openapi.yaml --config=docs-util/redocly/config.yaml`
* Open the documentation preview URL in a browser (http://127.0.0.1:8080)
* Expect responses to have their fields declared as `required`

packages/medusa/src/api/routes/admin/store/index.ts

@@ -33,6 +33,8 @@ export default (app) => {
 /**
  * @schema AdminStoresRes
  * type: object
+ * required:
+ *   - store
  * properties:
  *   store:
  *     $ref: "#/components/schemas/ExtendedStoreDTO"
@@ -44,6 +46,8 @@ export type AdminStoresRes = {
 /**
  * @schema AdminTaxProvidersList
  * type: object
+ * required:
+ *   - tax_providers
  * properties:
  *   tax_providers:
  *     type: array
@@ -57,6 +61,8 @@ export type AdminTaxProvidersList = {
 /**
  * @schema AdminPaymentProvidersList
  * type: object
+ * required:
+ *   - payment_providers
  * properties:
  *   payment_providers:
  *     type: array