Fix that style objects cannot be passed to element constructors

[hazington]

Description

I generally prefer to use style objects over style arrays in elements. But, if you pass a \PhpOffice\PhpWord\Style\Cell style element to the \PhpOffice\PhpWord\Element\Cell constructor then the $returnObject: true argument of the setNewStyle() method in the constructor completely ignores the passed style element, because the setNewStyle() method only checks if $styleValue is an array and returns $styleObject as empty style object otherwise. Imho, if $styleValue is a style object with the same type as $styleObject then the $returnObject: true should also be "ignored" and the passed style object should then be returned instead of the empty base style object.

Fixes # (issue)

Checklist:

• My CI is 🟢
• I have covered by unit tests my new code (check build/coverage for coverage report)
• I have updated the documentation to describe the changes (not applicable, bugfix did not change the behavior)
• I have updated the changelog

[coveralls]

coverage: 96.918%. remained the same
when pulling 15e69a6 on hazington:patch-abstract-element
into 43785fe on PHPOffice:master.

[hazington]

It took me a while to find the cause of the phpstan errors. Never imagined that there would be such a long list of ignored errors.

[hazington]

@Progi1984 Is there a chance to look over this pull request? I see that PhpWord transforms to a strict typed library and thus elements should accept style objects. This is also necessary for a better html to word implementation. At the moment you can't pass style objects since they are ignored.

[hazington]

@Progi1984 ?