Creates test request helper for API endpoints

Separates common utils into the medusa-core-utils package.
Sets up a testing environment where mocked models/services/etc. can be placed in
__mocks__ folder within its corresponding directory. The mocks will
automatically be registered in a awilix container only used for testing.

packages/medusa/src/utils/errors.js

@@ -1,36 +0,0 @@
-/**
- * @typedef MedusaErrorType
- *
- */
-export const MedusaErrorTypes = {
-  /** Errors stemming from the database */
-  DB_ERROR: "database_error",
-  INVALID_ARGUMENT: "invalid_argument",
-  INVALID_DATA: "invalid_data",
-  NOT_FOUND: "not_found"
-}
-
-/**
- * Standardized error to be used across Medusa project.
- * @extends Error
- */
-class MedusaError extends Error {
-  /**
-   * Creates a standardized error to be used across Medusa project.
-   * @param type {MedusaErrorType} - the type of error.
-   * @param params {Array} - Error params.
-   */
-  constructor(name, message, ...params) {
-    super(...params)
-
-    if (Error.captureStackTrace) {
-      Error.captureStackTrace(this, MedusaError)
-    }
-
-    this.name = name
-    this.message = message
-    this.date = new Date()
-  }
-}
-
-export default MedusaError

packages/medusa/src/utils/validator.js

@@ -1,4 +0,0 @@
-import Joi from "@hapi/joi"
-Joi.objectId = require("joi-objectid")(Joi)
-
-export default Joi