this.$databaseBind(...).then is not a function

[Todosiienko]

Reproduction

https://codesandbox.io/s/strange-borg-y41d0u?file=/src/App.vue

Steps to reproduce the bug

Hi, i don`t know why i have this issue, because documentation says
"If you need to wait for a binding to be ready before doing something, you can await the returned Promise:"

this.$databaseBind('user', dbRef(users, this.id).then(user => {
  // user will be an object if this.user was set to anything but an array
  // and it will point to the same property declared in data:
  // this.user === user
})
this.$databaseBind('documents', `query(documents,` orderByChild('creator'), equalTo(this.id))).then(documents => {
  // documents will be an array if this.documents was initially set to an array
  // and it will point to the same property declared in data:
  // this.documents === documents
})

or if i do something wrong please explane me

Expected behavior

have abilty to use DataSnapshot in .then() from $databaseBind method

Actual behavior

When we try to use .then on $databaseBind we get an error this.$databaseBind(...).then is not a function

Additional information

No response