fix: disableToolbar prop not behaving reactively

[VividLemon]

 <VuetifyTiptap
    v-model="interceptor"
    :extensions="extensions"
    :disabled="foo"
    :disable-toolbar="foo"
  />
  {{ foo }}
  <VBtn @click="foo = !foo">Toggle</VBtn>

const foo = ref(false)

When ran like this, VuetifyTiptap doesn't respect changing foo (disabled does)

This occurs because provide('disableToolbar', props.disableToolbar) passes the primitive true/false value, rather than a reactive value

const disableToolbar = inject<boolean>('disableToolbar', false) removes the default value. This is because undefined will be it's falsy replacement. Since we don't want to match types and create another ref we just use undefined

I was having an issue with the dev server, so I didn't test this. It seemed like a straightforward change, sorry.

[yikoyu]

Thank you for your contribution! It seems the PR was submitted to the wrong branch. Could you please submit it to the develop branch instead? Let me know if you need any help!
Thanks! 😊

[VividLemon]

Done