Usage of bindable in local template is not consistent with existing bindable

Extracted from #1086

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Our existing build time <bindable> is using attribute name and attribute. This is inline with Aurelia 1.

https://github.com/aurelia/aurelia/blob/071fd38ed69d74e34b04d0f9d62a3a15796ab9b8/packages-cjs/plugin-conventions/src/strip-meta-data.ts#L164-L171

But local template use attribute property. This is probably overlooked, need to change to name and attribute.

<template as-custom-element="foo-bar">
  <bindable property="prop"></bindable>

  Level One ${prop}
</template>
<foo-bar prop.bind="prop"></foo-bar>

[bigopon]

@Sayan751 yes it’s still inconsistent. I think we should have it as name + attribute

[bigopon]

I meant we could do it everywhere in 1 sweep later, to align 2 versions together, also to align local template & convention as well. The inconsistency probably should be resolved before alpha.