Related to https://github.com/cli/cli/issues/4201, documented the ability to install extensions using a full repo URL. Making a contribution to cli repo as well with similar documentation.
Co-authored-by: Ethan Palm <56270045+ethanpalm@users.noreply.github.com> Co-authored-by: Mislav Marohnić <mislav@github.com> Co-authored-by: Laura Coursen <lecoursen@github.com>