ignore a variable called 'package'

Hi. Though this is quite rare, but a statement like the following was wrongly deteted as a package (named 'or').
```
$package or
  die;
```

See also this commit for Parse::PMFile for a test. This was found while parsing the following module: 

https://metacpan.org/source/MSIMERSON/Mail-Toaster-5.42/lib/Mail/Toaster/Utility.pm#L1364