bug#33261: [substitute-urls] Fails when given only "berlin.guixsd.org"

[swedebugia]

$ guix package -i hello --substitute-urls=berlin.guixsd.org
substitute: guix substitute: error: berlin.guixsd.org: invalid URI
guix package: error: build failed: substituter `substitute' died 
unexpectedly

Adding "http://"; works:

$ guix package -i wget --substitute-urls=http://berlin.guixsd.org --dry-run
The following package would be upgraded:
   wget    1.19.5 → 1.19.5 
/gnu/store/7jd4nbdamp5bjvvi9acnk4nkk2dzyi71-wget-1.19.5

substitute: updating substitutes from 'http://berlin.guixsd.org'... 100.0%
The following derivations would be built:
   /gnu/store/y6yg5dsfam30v8d7f77bafysqjnbdhgj-profile.drv
   /gnu/store/qdgr96gw7jil08wqhp897mf8qzhhv32b-info-dir.drv
   /gnu/store/66apflyp7b41blxl7s6pv56kq5mfb8h4-fonts-dir.drv
/gnu/store/1d0njpsg6ch60hh5zdkg2lf173kqv32f-ca-certificate-bundle.drv
   /gnu/store/jba4idqg0q0rq0pvdal8scjf9176xx8z-manual-database.drv

$ which guix
/home/sdb/.config/guix/current/bin/guix

$ guix --version
guix (GNU Guix) 1f44934fb6e2cefccbecd4fa347025349fa9ff76

--
Cheers
Swedebugia