shared lexical variable in chained actions example

## grabbed from the docs
 
  # root action - captures one argument after it
  sub foo_setup : Chained('/') PathPart('foo') CaptureArgs(1) {
      my ( $self, $c, $foo_arg ) = @_;
      ...
  }
 
  # child action endpoint - takes one argument
  sub bar : Chained('foo_setup') Args(1) {
      my ( $self, $c, $bar_arg ) = @_;
      $c->log->info("my bar_arg is $bar_arg and my foo_arg is $foo_arg");
  }