Remove zend json from form elements

[dmanners]

Replace Zend_Json with just a basic json_encode in the configurable product block view test

Description

Since Zend1 is at EOL we should replace any usage of it's elements. For this case we are removing Zend_Json #9236

Fixed Issues (if relevant)

1. Upgrade ZF components. Zend_Json #9236: Upgrade ZF components. Zend_Json

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[dmanners]

Maybe hold off on this @davidalger just found something with the wysiwyg editor not sure if it is my change or develop.

[davidalger]

@dmanners Have you had a chance to review what you found with the wysiwyg editor? I can see that you pushed a new commit since your last comment, but on that one the tests are failing. I'm not sure why at first glance. Let me know. Thanks!

[dmanners]

@davidalger I found the issue. It was trying to work with an object and failing but I have had no time to work on the fix as yet.

[davidalger]

@dmanners Any chance you'll be able to circle back to this one some time soon?

[dmanners]

@davidalger been traveling for most of June so far. Guess July I will find some free time for this. 😭

[dmanners]

Thanks @okorshenko for the extra commit to fix the object issue. You are a star.