fix(omni up): 🐛 return code should be 1 on error (#267)

The `omni up` command was simply returning exit code `0` on error to set
things up, instead of erroring out properly.

This is now fixed.

src/internal/commands/builtin/up.rs

@@ -527,9 +527,11 @@ impl UpCommand {
                 let options = UpOptions::new().cache(self.cli_args().cache_enabled);
                 if let Err(err) = up_config.up(&options) {
                     omni_error!(format!("issue while setting repo up: {}", err));
+                    exit(1);
                 }
             } else if let Err(err) = up_config.down() {
                 omni_error!(format!("issue while tearing repo down: {}", err));
+                exit(1);
             }
         }