Add support for wildcards selecting compose files

[ndeloof]

fixes docker/compose#10857

[glours]

I’m wondering whether we should support this in compose-go, or if it should be handled on the client side instead?
If we decide to handle it within compose-go, I think we need to have a clear rule in the specification to ensure predictable behavior—something like loading files in alphabetical order.

[ndeloof]

I’m wondering whether we should support this in compose-go, or if it should be handled on the client side instead?

I looked into adding this to docker/compose first, but this is way simpler here.

I think we need to have a clear rule in the specification to ensure predictable behavior—something like loading files in alphabetical order.

Sure, here I'm using slices.Sort and this has to be well documented in the spec