BUGFIX: Implement missing method getObject in BehatTestHelper

[mficzel]

Resolves: #5188

Checklist

• Code follows the PSR-2 coding style
• Tests have been created, run and adjusted as needed
• The PR is created against the lowest maintained branch
• Reviewer - PR Title is brief but complete and starts with FEATURE|TASK|BUGFIX
• Reviewer - The first section explains the change briefly for change-logs
• Reviewer - Breaking Changes are marked with !!! and have upgrade-instructions

[mficzel]

Sadly this only solve the first issue and uncovers the next
The annotation "@fixtures" in method Neos\ContentRepository\Tests\Functional\Command\BehatTestHelper::beforeScenarioDispatcher() was never imported. Did you maybe forget to add a "use" statement for this annotation?

I think $someone familiar with the behat changes to flow 8.4 should take a look or at least give a hint what needs to change.