Avoid ternary operator in properties

[tas50]

What category of cop is this?:

Please try to select as few as possible.

• [ ] Chef/Deprecations - A cop that alerts on a deprecation in the Chef Infra Client
• [ ] Chef/Correctness - A cop that alerts when incorrect coding behavior is being used
• [ ] Chef/Sharing - A cop that alerts to missing functionality necessary for sharing cookbooks with others
• [ ] Chef/Style - A cop that alerts to a style best practice
• [ ] Chef/Modernize - A cop that alerts when a cookbook can be simplified or modernized with new functionality
• [ ] Chef/Effortless - A cop that alerts on code that must be resolved to move to the Effortless pattern
• [x] Chef/RedundantCode - A cop that detects redundant code regardless of Chef Infra release
• [ ] InSpec/Deprecations - A cop that alerts on a deprecation in the Chef InSpec

Describe the new cop:

We can avoid ternary operators that check if a value is an array before trying to make it an Array.

What it would trigger on:

property :template_helpers, [String, Array],
          description: 'Additional helper modules to include in the default site and config template',
          coerce: proc { |p| p.is_a?(Array) ? p : [p] }

What it would autocorrect to if applicable

property :template_helpers, [String, Array],
          description: 'Additional helper modules to include in the default site and config template',
          coerce: proc { |p| Array(p) }

[tas50]

Can't always assume this will be safe