Create workarounds:disablePerlUpdates preset

[HonkingGoose]

Describe the proposed change(s).

Create a new workarounds:disablePerlUpdates preset, with this content:

{
  "packageRules": [
    {
      "matchManagers": ["cpanfile"],
      "matchPackageNames": ["perl"],
      "enabled": false
    }
  ]
}

The new preset should also be put in the extends array of the workarounds:all preset, because we want to disable Perl updates by default. Users will have to opt-in explicitly.

Edit: changed the text above due to @rarkins's comment below.

Describe why we need/want these change(s).

Allow users that build applications to opt-in to Perl updates, if they don't need to care about other users.

[rarkins]

I think we can put it in the workarounds:all though, because users can opt into updating perl by adding the preset to ignorePresets

[HonkingGoose]

@rarkins I'm confused, because by default Renovate updates all package files that it finds... But you're saying you want users to opt-in to Perl updates? I must be missing some context here?

[rarkins]

Yes, that's right