Use reference-style links in CHANGELOG.md
Use reference-style links in CHANGELOG.md

leesdolphin/cobalt.rs,johannhof/cobalt.rs,cobalt-org/cobalt.rs,cobalt-org/cobalt.rs,leesdolphin/cobalt.rs,johannhof/cobalt.rs,cobalt-org/cobalt.rs,leesdolphin/cobalt.rs,johannhof/cobalt.rs,johannhof/cobalt.rs,leesdolphin/cobalt.rs,cobalt-org/cobalt.rs