Mark Naming/RescuedExceptionsVariableName as unsafe

[vfonic]

I just ran rubocop --safe-auto-correct and it made this autocorrect change:

-   rescue ActiveResource::Redirection => redirection
+   rescue ActiveResource::Redirection => e
      redirect_to redirection.response['Location']
    end

This is obviously a breaking change. I believe the easiest fix here is to mark this cop as unsafe, as, as far as I know, rubocop doesn't offer the extensive functionality for renaming a variable (redirection) across all of its usages.

I'm open for suggestions for better fix.

EDIT: I dug down and realized this has just recently been added by @anthony-robin (Thanks!) in this PR #6905. @anthony-robin, what do you think of marking this cop unsafe?

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[vfonic]

Not sure about this...

[bbatsov]

The cop itself is safe (meaning it doesn't generate false positives), only it's auto-correct should be marked as unsafe.

[Darhazer]

I've opened #6998 fixing the auto-correct to rename the variable inside the body as well

[vfonic]

The cop itself is safe (meaning it doesn't generate false positives), only it's auto-correct should be marked as unsafe.

@bbatsov I didn't know that's what "safe" means. Thanks!

@Darhazer awesome! :) Didn't know this is possible. I shouldn't have underestimated rubocop. :)
I'm gonna go ahead and close this PR, your PR is the one that should be merged.