[Fix #10436] Fix an error for Style/SoleNestedConditional raises exception when inspecting if ... end if ...

[ydah]

Fixes #10436.

This PR fixes an error for Style/SoleNestedConditional when code like the following:

if foo
  do_something
end if bar

---

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• Added tests.
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[ydah]

I updated this PR. Thanks a lot!

[koic]

Nice! Thank you for the fixing!