### Godot version

v4.0.beta.custom_build [d1e5903c6]

### System information

Arch Linux kernel 6.1.7-arch1-1 x86_64 OpenSSH 9.1p1-3

### Issue description

When using SSH remote deploy, if the extra args field is empty (the default) the ssh command is not executed with success because a single space is inserted in place of the extra args.

```
Creating temporary directory...
Executing: ssh -p 22  davi@192.168.1.50 mktemp -d
Exit code: 255, Output: ssh: Could not resolve hostname : Name or service not known

ssh: Could not resolve hostname : Name or service not known
```

If any valid argument is passed, the command is executed successfully, in the example below I duplicated the `-p 22`, which is ignored, to show that it is not a problem of the hostname passed.

```
Executing: ssh -p 22 -p 22 davi@192.168.1.50 mktemp -d
Exit code: 0, Output: /tmp/tmp.DwFObXBL2s
```

This is infuriating for when you have non-interactive authentication configured in ssh-agent and just the hostname is needed for the connection.
This occurs for both SSH and SCP.

### Steps to reproduce

1. Enable a project to deploy with ssh
2. Fill only the hostname
3. Try to deploy
4. See the error on the console

### Minimal reproduction project

N/A
args.push_back(p_preset->get("codesign/timestamp_server_url"));
#endif
		} else {
			add_message(EXPORT_MESSAGE_WARNING, TTR("Code Signing"), TTR("Invalid timestamp server."));
			return FAILED;
		}
	}
	
#ifdef WINDOWS_ENABLED
	args.push_back("/fd");
#else
	args.push_back("-h");
#endif
	if ((int)p_preset->get("codesign/digest_algorithm") == 0) {
		args.push_back("sha1");
	} else {
		args.push_back("sha256");
	}
	
	if (p_preset->get("codesign/description") != "") {
#ifdef WINDOWS_ENABLED
		args.push_back("/d");
#else
		args.push_back("-n");
#endif
		args.push_back(p_preset->get("codesign/description"));
	}
	
	PackedStringArray user_args = p_preset->get("codesign/custom_options");
	for (int i = 0; i < user_args.size(); i++) {