Update Composer repos with all releases

According to this URL,Packagist Semver Checker, this module does not have a publicly accessible alpha release.

Perhaps Composer gets releases from other places, but I wanted to make sure that other modules, specifically default_content_deploy are able to see release alpha8 and future releases.

(This whole thing might hinge on a misunderstanding of composer mechanics from my side. If so, my apologies, and please disregard and close.)

Thanks for the great module!