Support signing .rdp files

**Is your feature request related to a problem? Please describe.**
Since dealing with `.rdp` files is getting more strict in terms of security, it would be helpful to be able to sign these files too. (https://learn.microsoft.com/en-us/windows-server/remote/remote-desktop-services/remotepc/understanding-security-warnings)

**Describe the solution you'd like**
Be able to sign `.rdp` files too

**Describe alternatives you've considered**
There is a signing tool for RDP files, but this doesn't work with Trusted Signing or Key Vault. (https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/rdpsign)

**Additional context**
0.9.1-beta.26179.1+21990c8ec7ace15c7dcf334de241016627380ac0