check-meta: Fix typos in comment and error message (#431962)

      however ${getNameWithVersion attrs} only has the outputs: ${builtins.concatStringsSep ", " actualOutputs}

      and is missing the following ouputs:

      and is missing the following outputs:

      ${concatStrings (builtins.map (output: "  - ${output}\n") missingOutputs)}

    '';

          else if valid == "warn" then

            (handleEvalWarning { inherit meta attrs; } { inherit (validity) reason errormsg; })

          else

            throw "Unknown validitiy: '${valid}'"

            throw "Unknown validity: '${valid}'"

        );

      };