FIX Allow recipe-testing ^4

[emteknetnz]

Issue silverstripe/.github#199

[GuySartorelli]

Might as well just use * or >=2 at this point 😅

[emteknetnz]

Good idea though I don't think we use either of those anywhere else, the standard seems be to be just use a combination of ^ and || which is good in that it's better at preventing unexpected behavior so I think we should just keep using
those

[GuySartorelli]

I don't think we use either of those anywhere else

That's not a reason to not do it here, if it makes sense to do it here. I think it makes sense to do the forward-compatible thing here.

That said, it doesn't matter enough for me to push this back. Just adding a note here that when we encounter a problem caused by this come CMS 7 time, we should update to use forward-compatible constraint at that time so we don't have to touch this every time we do a major release.