Use more idiomatic Vitest in the testing suite (#1245)

* Use vitest except where possible and organize tests

* Use vi.fn() instead of CallTracker in 'deprecated' helper

- CallTracker has been deprecated in Node.js
- vi.fn() is probably more familiar to Vitest users

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Co-authored-by: Artur Müller <me@arturmuller.com>

package.json

@@ -34,7 +34,6 @@
     "eslint": "^8.57.0",
     "eslint-config-prettier": "^9.1.0",
     "eslint-plugin-prettier": "^5.1.3",
-    "is-email": "^1.0.0",
     "is-url": "^1.2.4",
     "is-uuid": "^1.0.2",
     "lodash": "^4.17.15",

test/validation/refine/invalid.ts

@@ -1,7 +1,6 @@
-import isEmail from 'is-email'
 import { string, refine } from '../../../src'
 
-export const Struct = refine(string(), 'email', isEmail)
+export const Struct = refine(string(), 'email', (value) => value.includes('@'))
 
 export const data = 'invalid'
 

test/validation/refine/valid.ts

@@ -1,7 +1,6 @@
-import isEmail from 'is-email'
 import { string, refine } from '../../../src'
 
-export const Struct = refine(string(), 'email', isEmail)
+export const Struct = refine(string(), 'email', (value) => value.includes('@'))
 
 export const data = 'name@example.com'