chore(utils): clean util package deps (#4146)

packages/utils/src/common/is-email.ts

@@ -1,6 +1,16 @@
-import { isEmail } from "class-validator"
 import { MedusaError } from "./errors"
 
+const EMAIL_REGEX =
+  /^(([^<>()[\]\\.,;:\s@"]+(\.[^<>()[\]\\.,;:\s@"]+)*)|.(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/
+
+/**
+ * Check whether provided string is an email.
+ * @param email - string to check
+ */
+function isEmail(email: string) {
+  return email.toLowerCase().match(EMAIL_REGEX)
+}
+
 /**
  * Used to validate user email.
  * @param {string} email - email to validate