Adds a new command: 'spo site admin list'. Closes #5882

[mkm17]

Adds a new command: 'm365 spo site admin list'.

Closes #5882

Hello, could you please review the pull request below? It contains a new command for retrieving a list of administrators for SharePoint sites.

I still have some concerns, so please confirm the following:

• Is the function to obtain the SiteId based on the SiteUrl suitable for users who are only SharePoint admins? (Similar to what is used in spo site list)
• Is the endpoint _api/sites/owner the correct one to retrieve the primary admin of the site in regular cases (not '--asAdmin')?
• Is it acceptable to not provide information about PrincipalType and Id in the '--asAdmin' case, since it is not provided by the /_api/SPO.Tenant/GetSiteAdministrators endpoint?

I believe I've made all the necessary changes. If everything looks good, this command could be a base for other tasks mentioned. #5874

[Jwaegebaert]

Thanks @mkm17, we'll try to review it asap!

[mkm17]

Thanks @Adam-it for the review, I will check it and comeback soon !

[Adam-it]

ready to merge 🚀

[mkm17]

@Adam-it Thank you very much for your time!

[Adam-it]

merged manually 👍 Thank you for your awesome contribution 👏. You Rock 🤩