[Options API] outdated alert on provide/inject page

[jacekkarczmarczyk]

https://vuejs.org/guide/components/provide-inject.html#working-with-reactivity

I don't know if this change is implemented, if it is I think the alert could be removed (or the information could be changed to For Vue 3.2 or older the above usage requires blah blah), otherwise it should be updated (This will become the default behavior in Vue 3.3 => This will become the default behavior in Vue 3.4 or whatever).