This adds an object cache drop-in to the `tests/phpunit/includes` directory to avoid relying on and having to copy from an external repository.
It also removes a stray character that was mistakenly included in [50210].
Follow up to [50210], [50314].
Unprops desrosj.
See #50401.
git-svn-id: https://develop.svn.wordpress.org/branches/4.4@50316 602fd350-edb4-49c9-b593-d223f7449a82
