Make `Performance/Sum` aware of arrays

[viralpraxis]

Expected behavior

Currently, RuboCop suggest to correct expressions like

%w[a* b*].map { |e| Dir.glob(e) }.reduce(&:+)

to

%w[a* b*].map { |e| Dir.glob(e) }.sum

Since Dir.glob is known to return an array we can autocorrect to sum([]) instead. This can be generalized to other stdlib methods returning arrays

Actual behavior

Unsafe autocorrection is %w[a* b*].map { |e| Dir.glob(e) }.sum, which is invalid.

Steps to reproduce the problem

N/A

RuboCop version

main