Add Behat step for installing WordPress with specific version #552

Job	Run time
code-quality / Lint GitHub Actions workflows	3s
code-quality / Spell check	2s
code-quality / Lint Gherkin Feature files	3s
code-quality / PHPStan	3s
code-quality / Lint PHP files	3s
code-quality / PHPCS	1s
	15s

Provide feedback