Don't do it
I can't say I've done that before, but you should not remove that file. It is there for the use of Plesk (and it's included programs) to use when needed for authentication with different Plesk components (like the psa database)...
The file is not a security risk if the permissions are only RW for psaadm and nobody else. It's never going to be readable by Apache.
If someone gets root or psaadm access, then they're already either going to have that password or have access to EVERYTHING on the box, not just that file.
Jordan