add min and max to list of false positives for Style/SymbolProc

[mollerhoj]

This PR fixes a false positive for Style/SymbolProc when using Array#min and Array#max

The cop incorrectly assumes that the two invocations below are the same, and recommends the former:

> [1,2,3].min(&:to_i)
ArgumentError: wrong number of arguments (given 1, expected 0)
> [1,2,3].min { |x| x.to_i }
=> 1

Style/SymbolProc is already marked as unsafe, but it avoids avoidable issues.

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• The PR relates to only one subject with a clear title and description in grammatically correct, complete sentences.
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• Squashed related commits together.
• Added tests.
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[koic]

Thanks!