[Feature Request] pipelines create should support Github Enterprise

**Is your feature request related to a problem? Please describe.**
Yes. I am trying to automate pipeline creation for a client and am unable to do so through the Azure DevOps CLI extension because it does not support Github Enterprise.

**Describe the solution you'd like**
"ghe" or "githubenterprise" should be an allowed value for `--repository-type`, and pipeline creation from a Github Enterprise repository should work.

This may require either adding an additional parameter for the github api base url, or parsing the domain from the `--repository` argument and then appending it and using `https://{domain}/api/v3/`.

**Additional context**
Error received when `--repository-type` is not provided and remotes of local repo point to Github Enterprise:
>The following arguments are required: --repository-type. Check command help for valid values.

Error received when `--repository-type github` is provided along with a `--service-connection` that resolves to a GHE service connection and a `--repository` that points to a GHE repo:
>Unable to configure a service on the selected GitHub repository. GitHub returned the error 'Bad credentials'.

Inizia dal comando `pipelines create` e dalla relativa convalida di `--repository-type`, quindi segui come vengono gestite le connessioni al servizio GitHub e gli URL dei repository. Il lavoro è completato quando è possibile selezionare repository GitHub Enterprise e la creazione della pipeline ha esito positivo, incluso il comportamento richiesto dell'URL di base dell'API GitHub Enterprise.

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