Read the workspace's single sign-on connection

`redirectUri` is what to register at the provider; `txtValue` is the TXT record the domain needs at `_cloady.<domain>` before it can be saved.

curl -X GET "https://example.com/api/workspaces/string/sso"

{  "sso": {    "domain": "string",    "issuer": "string",    "clientId": "string"  },  "redirectUri": "string",  "txtValue": "string"}