Add new config `arguments_or_slashes` to `Rails/FilePath`

[tejasbubane]

Config to just check for usage of File.path, but doesn't care about arguments to Rails.root.join

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• [ ] Commit message starts with [Fix #issue-number] (if the related issue exists).
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• [x] Added tests.
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[koic]

I think the concept is good 👍 However I doubt the addition of the new parameter EnforcedStyle: arguments_or_slashes. I think this cop should probably be updated to accept multiple EnforcedStyle configuration using AllowMultipleStyles: true.

# .rubocop.yml
Rails/FilePath:
  EnforcedStyle:
    - slashes
    - arguments

Refer: https://github.com/rubocop-hq/rubocop/pull/6649

[tejasbubane]

@koic Looks like rubocop does not support multiple styles for EnforcedStyle yet - CI error.

[koic]

Yup. About implementation should investigate the cause of the error and resolve it. I haven't reached the cause yet. AllowMultipleStyles provides new representation option for user, but it is a relatively new parameter and needs to be grown when something is missing.