Fetch repos doesn't support organisations

Say I want to get all my Github Org's repos info, for data analysis. Not just the public repos, but also the private/internal repos.

The endpoints are different for organisation, and this tool doesn't take it into account:
https://github.com/dogsheep/github-to-sqlite/blob/ace13ec3d98090d99bd71871c286a4a612c96a50/github_to_sqlite/utils.py#L453
https://github.com/dogsheep/github-to-sqlite/blob/ace13ec3d98090d99bd71871c286a4a612c96a50/github_to_sqlite/utils.py#L455

The endpoints for organisation repos is instead ([source](https://docs.github.com/en/rest/repos/repos#list-organization-repositories)):
`url = "https://api.github.com/orgs/{}/repos".format(username)`

Let's add support for organisations repo scraping.

Inizia in github_to_sqlite/utils.py alle righe indicate intorno a 453-455 e confronta l’endpoint corrente dei repository con il organization-repositories endpoint di GitHub. Segui l’entry point di fetch-repositories, quindi verifica che i repository dell’organizzazione, inclusi quelli privati e interni, vengano recuperati e archiviati come previsto.

Scritto dal modello di indicizzazione a partire dal testo della issue.