[6.x] Fixed vueAttribute for older Vue 2.x projects

[myMartek]

No description provided.

[myMartek]

The latest release contains a bug:

For vue 2.0 projects there is a return el.__vue.'.$key.';' statement even though the correct way to query vue is using __vue__

[driesvints]

Ping @derekmd

[derekmd]

Whoops, sorry, don't know how that snuck through.

[driesvints]

@derekmd no worries. Does the fix look good to you?

[derekmd]

Yup, it's good. Code snippet from pre-Vue 3 fixes:

dusk/src/Concerns/MakesAssertions.php

Lines 1103 to 1108 in bc9fd27

	return $this->driver->executeScript(
	"var el = document.querySelector('".$fullSelector."');".
	"return typeof el.__vue__ === 'undefined' ".
	'? JSON.parse(JSON.stringify(el.__vueParentComponent.ctx)).'.$key.
	': el.__vue__.'.$key
	);