fix: toString utils should unref the Ref<T>

[enpitsuLin]

fix #12884

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• Bugfix
• Feature
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[enpitsuLin]

Vue3 has a replacer parameter in JSON.stringify that call in toDisplayString but as same purpose toString doesn't

I'm not sure if I need to add that parameter or just do unref for Ref<T>

[LingRen]

don't depend v3, use type

[yyx990803]

• It should use replacer, otherwise it won't unwrap nested refs.
• It should not depend on v3, as it causes a circular dependency and causes runtime errors in the built version of Vue.
  See ae3e4b1