Use the key as a property rather than and index

ConsolidateArrayValuesByKey() currently checks the object for a $ValueKey property then tries to access the $Key as an index on the object. This fails.

Use the $Key property of the object as an index instead for intended behavior.

I searched the code base for uses of this function with at least 3 parameters and found 6 occurrences. Everyone of those occurrences passes an array rather than an object, so this may be a currently unused code path.

The type of data I was trying to consolidate was in the form:

    Array
    (
        [0] => stdClass Object
            (
                [ActionID] => 5
                [Name] => Promote
                [Description] => This post deserves to be featured on the best of page!
                [Tooltip] => Click me if this content should be featured.
                [CssClass] => ReactPointUp
                [AwardValue] => 5
                [Permission] => Garden.Curation.Manage
                [Sort] => 0
            )
        [1] => stdClass Object
            (
                [ActionID] => 1
                [Name] => Awesome
                [Description] => I approve!
                [Tooltip] => This indicates casual approval
                [CssClass] => ReactHeart
                [AwardValue] => 1
                [Permission] => Yaga.Reactions.Add
                [Sort] => 1
            )
        [2] => stdClass Object
            (
                [ActionID] => 6
                [Name] => WTF
                [Description] => What just happened?
                [Tooltip] => Click me if you don't know what is going on.
                [CssClass] => ReactShocked2
                [AwardValue] => 1
                [Permission] => Yaga.Reactions.Add
                [Sort] => 2
            )
        [3] => stdClass Object
            (
                [ActionID] => 4
                [Name] => Insightful
                [Description] => This is insightful!
                [Tooltip] => Click me if this post made you think in a new way
                [CssClass] => ReactEye2
                [AwardValue] => 1
                [Permission] => Yaga.Reactions.Add
                [Sort] => 3
            )
        [4] => stdClass Object
            (
                [ActionID] => 3
                [Name] => HEH
                [Description] => This indicates you are funny.
                [Tooltip] => That is funny!
                [CssClass] => ReactWink
                [AwardValue] => 1
                [Permission] => Yaga.Reactions.Add
                [Sort] => 4
            )
        [5] => stdClass Object
            (
                [ActionID] => 2
                [Name] => Meh
                [Description] => I disapprove!
                [Tooltip] => This indicates casual disapproval
                [CssClass] => ReactNeutral
                [AwardValue] => 0
                [Permission] => Yaga.Reactions.Add
                [Sort] => 5
            )
    )


With my call being `ConsolidateArrayValuesByKey($Actions, 'ActionID', 'Name');`. This threw the following error before the proposed patch:

`Fatal error: Cannot use object of type stdClass as array in /www/vanilla21/library/core/functions.general.php`