update testing configurations

integration-tests/setup.js

@@ -0,0 +1,3 @@
+const { MetadataStorage } = require("@mikro-orm/core")
+
+MetadataStorage.clear()

jest.config.js

@@ -15,6 +15,7 @@ module.exports = {
   testEnvironment: "node",
   moduleFileExtensions: ["js", "ts", "json"],
   modulePathIgnorePatterns: ["dist/", "<rootDir>/.medusa/"],
+  setupFiles: ["./integration-tests/setup.js"],
 };
 
 if (process.env.TEST_TYPE === "integration:http") {