feat: replace no only tests with vitest (!2)

This gives us a much more robust configuration for our rules. Additionally, it expects tests to be converted to the `expect` API.

Reviewed-on: https://codeberg.org/nhcarrigan/eslint-config/pulls/2
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

package.json

@@ -35,11 +35,11 @@
     "@stylistic/eslint-plugin": "2.3.0",
     "@typescript-eslint/eslint-plugin": "rc-v8",
     "@typescript-eslint/parser": "rc-v8",
+    "@vitest/eslint-plugin": "1.1.4",
     "eslint-config-prettier": "9.1.0",
     "eslint-plugin-deprecation": "3.0.0",
     "eslint-plugin-import": "2.29.1",
     "eslint-plugin-jsdoc": "48.8.3",
-    "eslint-plugin-no-only-tests": "3.1.0",
     "eslint-plugin-prettier": "5.2.1",
     "eslint-plugin-sort-keys-fix": "1.1.2",
     "eslint-plugin-unicorn": "55.0.0",