Fix infinite loop between Layout/IndentationWidth and Layout/RescueEnsureAlignment autocorrection

[dvandersluis]

There was an autocorrect infinite loop between Layout/IndentationWidth and Layout/RescueEnsureAlignment, as well as a false positive, for actually correct cases such as

def a
rescue StandardError
ensure
  a
end

due to Layout/IndentationWidth getting confused by there being no body before the rescue. It will now only check indentation of a rescue node if it has a body.

I also added a test to make sure the two cops autocorrect properly when used in unison.

Fixes standardrb/standard#112.

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• Added tests.
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[koic]

Thanks!