Set default log level fwhen launching vagrant ruby

internal/cli/main.go

@@ -247,6 +247,9 @@ func logger(args []string) ([]string, hclog.Logger, io.Writer, error) {
 		}
 	}
 
+	// Set default log level
+	_ = os.Setenv("VAGRANT_LOG", "fatal")
+
 	// Process arguments looking for `-v` flags to control the log level.
 	// This overrides whatever the env var set.
 	var outArgs []string