head_title_array variable deprecated in favour of head_title

We are avoiding using "type" names in twig templates, therefore we removed the array suffix in the variable name head_title_array sent to html.html.twig template. Additionally we avoid rendering the parts before the template to avoid the necessary work in preprocess.

Before:

{{ head_title }}

or

{{ head_title_array|join(' • ') }}

or

{{ head_title_array.slogan }}

After:

{{ head_title|join(' • ') }} 

Or a part of the head title specifically like this:

{{ head_title.slogan }}