Add missing preference for ObjectManager\ConfigInterface in integrati…

[schmengler]

…on tests

Description

A missing preference caused failures in integration tests as soon as the object manager config interface occured in the dependency graph of an instantiated class.

Fixed Issues (if relevant)

1. "Cannot instantiate interface Magento\Framework\Interception\ObjectManager\ConfigInterface" error in integration tests #12844: "Cannot instantiate interface Magento\Framework\Interception\ObjectManager\ConfigInterface" error in integration tests

Manual testing scenarios

See Issue

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)

[mzeis]

Thanks Fabian for this pull request! As I leave tomorrow morning for Christmas holidays I'm afraid I will only be able to finish the processing after the holidays (even when it's just a small change).

I hope you understand. Happy Christmas! 🎄

[schmengler]

No problem, I'm enjoying my holidays too without work 😄 Happy new year!

[mzeis]

Thanks again @schmengler for your fix. It has been merged into 2.2-develop!