Modify the `default` suite to use the `saltmajorversion` InSpec input
rather than the `version` variable in `pkgs_spec.rb`.

```
Offenses:

test/integration/v3000-py2/controls/pkgs_spec.rb:10:5: C: [Correctable]
Style/WordArray: Use ['Salt Minion'] for an array of words.
(https://rubystyle.guide#percent-w)
    %w[Salt\ Minion]
    ^^^^^^^^^^^^^^^^
test/integration/v3000-py3/controls/pkgs_spec.rb:10:5: C: [Correctable]
Style/WordArray: Use ['Salt Minion'] for an array of words.
(https://rubystyle.guide#percent-w)
    %w[Salt\ Minion]
    ^^^^^^^^^^^^^^^^
test/integration/v3001-py3/controls/pkgs_spec.rb:10:5: C: [Correctable]
Style/WordArray: Use ['Salt Minion'] for an array of words.
(https://rubystyle.guide#percent-w)
    %w[Salt\ Minion]
    ^^^^^^^^^^^^^^^^
test/integration/v3002-py3/controls/pkgs_spec.rb:10:5: C: [Correctable]
Style/WordArray: Use ['Salt Minion'] for an array of words.
(https://rubystyle.guide#percent-w)
    %w[Salt\ Minion]
    ^^^^^^^^^^^^^^^^
test/integration/v3003-py3/controls/pkgs_spec.rb:10:5: C: [Correctable]
Style/WordArray: Use ['Salt Minion'] for an array of words.
(https://rubystyle.guide#percent-w)
    %w[Salt\ Minion]
    ^^^^^^^^^^^^^^^^

19 files inspected, 5 offenses detected, 5 offenses auto-correctable
```

Resolves issues introduced in 24ebbb4e0c.

* https://travis-ci.org/github/myii/salt-formula/jobs/692337807#L2366-L2381
  - `opensuse` now has `3000.3` available
* Simplification is useful anyway, even without this (could still use `case`)

* https://docs.saltstack.com/en/latest/topics/releases/3000.3.html
* https://docs.saltstack.com/en/latest/topics/releases/2019.2.5.html