[users] tag functionality

[dmgorsky]

As of https://docs.github.com/en/rest/users?apiVersion=2022-11-28 ,
the following URL handlers in octocrab are missing:

• /user/blocks
• /user/ssh_signing_keys/{ssh_signing_key_id}
• /user/emails
• /user/gpg_keys/{gpg_key_id}
• /user/following
• /user/email/visibility
• /user/gpg_keys
• /users/{username}/following
• /user/public_emails
• /users/{username}/gpg_keys
• /users/{username}/followers
• /user/followers
• /users/{username}
• /user/keys
• /users
• /users/{username}/keys
• /users/{username}/following/{target_user}
• /user/social_accounts
• /user/following/{username}
• /users/{username}/hovercard
• /users/{username}/ssh_signing_keys
• /user/keys/{key_id}
• /user/blocks/{username}
• /user/ssh_signing_keys
• /users/{username}/social_accounts