Improve Naming/RescuedExceptionsVariableName autocorrection

[Darhazer]

Follow up on #6994, this PR adds renaming of the variable references inside the resbody

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• Wrote good commit messages.
• Commit message starts with [Fix #issue-number] (if the related issue exists).
• Feature branch is up-to-date with master (if not - rebase it).
• Squashed related commits together.
• Added tests.
• Added an entry to the Changelog if the new code introduces user-observable changes. See changelog entry format.
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[bbatsov]

Nicely done!