SSH: Cannot SSH when config includes a RemoteCommand

[dbowling]

Describe the bug

When using RemoteCommand in my SSH config (using MacOS) I get the following error: Cannot execute command-line and remote command.

Hosts that do not use the RemoteCommand setting perform SSH correctly.

To Reproduce

Steps to reproduce:

1. Edit .ssh/config and add a host with a RemoteCommand, such as RemoteCommand tmux new -A -s anynameyoulike
2. run the SSH command ssh hostname

Expected behaviour

SSH to connect to the server and run the command.

Screenshots

No response

Operating System

MacOS

OS Version

12.0.1

Additional context

Hosts with `ProxyCommand ssh -W %h:%p proxyhostname.tld` are not impacted.

[elviskahoro]

@dbowling
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• SSH Support V1 #502
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