Add support for new vue version

[jhgeluk]

Hi, I'm trying to get this component to work. But it doesn't seem to work for new versions of vue.

Versions:
Vue: ^3.0.0
Vuex: ^4.0.0
Vue CLI: 4.5.9

Error:

VueQueryBuilder.common.js?9a97:4275 Uncaught (in promise) TypeError: Cannot read property '_c' of undefined

 at Proxy.render (VueQueryBuilder.common.js?9a97:4275)
 
 at renderComponentRoot (runtime-core.esm-bundler.js?5c40:846)

 at componentEffect (runtime-core.esm-bundler.js?5c40:4280)

 at reactiveEffect (reactivity.esm-bundler.js?a1e9:42)

 at effect (reactivity.esm-bundler.js?a1e9:17)

 at setupRenderEffect (runtime-core.esm-bundler.js?5c40:4263)

 at mountComponent (runtime-core.esm-bundler.js?5c40:4222)

 at processComponent (runtime-core.esm-bundler.js?5c40:4182)

 at patch (runtime-core.esm-bundler.js?5c40:3791)

 at mountChildren (runtime-core.esm-bundler.js?5c40:3975)

Is there any fix for this?

[lukasjelonek]

I adapted the component to vue-3 and bootstrap-5, but made a few changes that probably won't be compatible to the version in this repository. You can check it out at https://github.com/lukasjelonek/vue-query-builder.
I am interested to submit these changes to the original repository, but at the moment I don't know how to keep them compatible to vue-2 and vue-3 at the same time. Is there someone who may help?