### 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
String err;
	bool valid = false;
	// Look for export templates (custom templates).
	bool dvalid = false;
	bool rvalid = false;
	if (p_preset->get("custom_template/debug") != "") {
		dvalid = FileAccess::exists(p_preset->get("custom_template/debug"));
		if (!dvalid) {
			err += TTR("Custom debug template not d.") + "\n";
		}
	}
	if (p_preset->get("custom_template/release") != "") {
		rvalid = FileAccess::exists(p_preset->get("custom_template/release"));
		if (!rvalid) {
			err += TTR("Custom release template not d.") + "\n";
		}
	}
	// Look for export templates (official templates, check only is custom templates are not set).
	if (!dvalid || !rvalid) {
		dvalid = exists_export_template("macos.zip", &err);
		rvalid = dvalid; // Both in the same ZIP.
	}
	valid = dvalid || rvalid;
	r_missing_templates = !valid;
	if (!err.is_empty()) {
		r_error = err;
	}
	return valid;
}
bool EditorExportPlatformMacOS::has_valid_project_configuration(const Ref<EditorExportPreset> &p_preset, String &r_error) const {