title: ipyvuetify can't set prop to static text
body: <p>Hello nice people of Internet ;)</p>
  <p>New job, new language. I need to modify Ipyvuetify  Vue code in Jupiter notebooks to use static props.</p>
  <p>I was able to throw together simple vue example<br />
  where I am able to set prop of child component via assigned static text in declarative way in vue file.
  And it works just fine in js variant. <a href="https://jsfiddle.net/wu9bxL1n/1/" rel="nofollow noreferrer">https://jsfiddle.net/wu9bxL1n/1/</a></p>
  <p>But the same  approach doesn't seem to work at all in ipyvuetify syntax. No error no nothing. Static string assigned to child prop is just being silently ignored and I can't seem to find anything in docs as for why. What did I missed ?</p>
  <p>Here is the smallest possible code in ipyvuetify syntax copy/pastable to Jupiter notebook.</p>
  <pre><code>import ipyvuetify as v
  import traitlets
  ​
  class AA(v.VuetifyTemplate):
      template = traitlets.Unicode('''
      &lt;template&gt;
          &lt;v-card-title&gt;{{label}}&lt;/v-card-title&gt;
      &lt;/template&gt;
      &lt;script&gt; export default { name: &quot;aa&quot;, props: ['label'] } &lt;/script&gt;''').tag(sync=True)
      
      label = traitlets.Unicode('But this is showing default text instead').tag(sync=True)
  ​
  class BB(v.VuetifyTemplate):
      template = traitlets.Unicode('''
      &lt;template&gt;
      &lt;div&gt;
        &lt;v-text-field label=&quot;This text was set statically&quot; &gt;&lt;/v-text-field&gt;
        &lt;aa           label=&quot;This text was set statically&quot;&gt;&lt;/aa&gt;
      &lt;/div&gt;
      &lt;/template&gt;''').tag(sync=True)
     
      components = traitlets.Dict(default_value={'aa': AA()}).tag(sync=True, **v.VuetifyTemplate.class_component_serialization)
  ​
  BB()
  </code></pre>
  <p>​---</p>
  <pre><code>Output:
  
  This text was set statically
  But this is showing default text instead
  </code></pre>