ServerTravel command doesn't work in PIE using seamless travel

The "servertravel" command doesn't function when running ShooterGame in Editor.

A warning will show up in the Output Log:
LogWorld:Warning: UWorld::ServerTravel: Seamless travel currently NOT supported in single process PIE.

This warning will appear whether you're using single process or not.

However, when running the ShooterGame with -game with a server and client the servertravel command works fine, but the "setall" command is not recognized.

Regression: Yes
Broken: 2658896
Worked: 2522625

1. Open ShooterGame in Editor.
2. Select the Play drop down > Set the Number of Players to 2 and net mode to Listen
3. Select Play in Viewport
4. Switch to the server. Press ~ (tilde). Enter the command "servertravel sanctuary"

Results:
Nothing

Expected Results:
The server and the client both travel to the Sanctuary map.