How do the change the shell used for VS Code's integrated terminal when I connect to an remote ssh workspace?
You can use remote setting to change the shell for each host. To do this, open the remote workspace in VS Code and run the Open Remote settings
command:
Set terminal.integrated.shell.linux
to point to your shell and save the file:
"terminal.integrated.shell.linux": "/usr/bin/fish"
The remote settings apply to all workspaces you open on a given host, but must be configured for each host you connect to.