[Fix #9843] Fix Style/RedundantSelf to allow conditional nodes to use self in the condition when a variable named is shadowed inside

[dvandersluis]

Previously, Style/RedundantSelf registered false positives when a condition used self to avoid shadowing a local variable:

a = self.a if self.a

This was because the condition was not correlated to the lvar assign because they happen at different times. This is now fixed so if, unless, while and until nodes are covered.

Fixes #9843.

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[dvandersluis]

Failing CI seems like a false negative.

[koic]

This looks good! Thank you for catching up with while, until, and masgn cases!