feature request: allow usage with private repos

[da1z]

hey. i would like to use it with private repos. would you be willing to accept PR with it?
from what i see and tried locally would be as easy as allow usage for github token when checking for repo existance. then git clone will be handled by ssh key already on my machine.

   const apiUrl = `https://api.github.com/repos/${owner}/${repo}`;
+  const token = process.env.OPENSRC_GITHUB_TOKEN;
 
   const response = await fetch(apiUrl, {
     headers: {
       Accept: "application/vnd.github.v3+json",
       "User-Agent": "opensrc-cli",
+      ...(token ? { Authorization: `Bearer ${token}` } : {}),
     },
   });