hotfix: enable to call Enterprise from octo buffer

The current build uses github.com always in octo buffers, so it cannot
get candidates from GitHub Enterprise. To solve this, this fix gets the
hostname from `octo.config` module.

lua/cmp_git/utils.lua

@@ -72,7 +72,7 @@ M.get_git_info = function(remotes, opts)
         local host, owner, repo = nil, nil, nil
 
         if vim.bo.filetype == "octo" then
-            host = "github.com"
+            host = require("octo.config").get_config().github_hostname
             local filename = vim.fn.expand("%:p:h")
             owner, repo = string.match(filename, "^octo://(.+)/(.+)/.+$")
         else