Add errors parameter

[manuelmeurer]

Resolves #47

---

Before the change?

MyError = Class.new(StandardError)

begin
  Octopoller.poll retries: 3 do
    # Do something that might raise MyError.
  rescue MyError => cause_error
    :re_poll
  end
rescue Octopoller::TooManyAttemptsError => error
  # To access the error, which caused the Octopoller::TooManyAttemptsError,
  # I must access `cause_error`, since `error.cause` is nil.
end

After the change?

MyError = Class.new(StandardError)

begin
  Octopoller.poll retries: 3, errors: [MyError] do
    # Do something that might raise MyError.
    # It will be retried 3 times automatically.
  end
rescue Octopoller::TooManyAttemptsError => error
  # Here I can access the error, which caused the Octopoller::TooManyAttemptsError,
  # via `error.cause`.
end

Pull request checklist

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)

Does this introduce a breaking change?

Please see our docs on breaking changes to help!

• Yes
• No

[github-actions]

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[manuelmeurer]

I haven't added tests or updated the docs yet, happy to do so if this feature is welcomed! 😄