Mailu domain managers can take over higher-privileged accounts

Mailu is a mail server distributed as a set of Docker images. Prior to 8577c929b4ade04d3cd4210cf036601abd793556, a domain manager targeting an administrative account or another domain manager with greater privileges can reset passwords or obtain tokens for that account. This authorization failure allows a domain manager to take over a higher-privileged account and exercise that account's permissions. This vulnerability is addressed by commit 8577c929b4ade04d3cd4210cf036601abd793556.