post https://rls.congacloud.com/api/sign/v1/cs-authenticationTokens/signer/singleUse
Creates a token that can be used to obtain a valid session for a particular signer of an existing package
so they can sign the package. This single-use token is restricted to a single package and expires after 30 minutes
(this is configurable). This token allows you to log in through a Get to the
%2Fauth?senderAuthenticationToken=VALUE%26target=http://environment/destination.
The destination must be a valid destination for a signer.