Add new Performance/RedundantEqualityComparisonBlock cop

[koic]

This PR adds new Performance/RedundantEqualityComparisonBlock cop.

The cop checks for uses Enumerable#all?, Enumerable#any?, Enumerable#one?, and Enumerable#none? are compared with === or similar methods in block.

By default, Object#=== behaves the same as Object#==, but this behavior is appropriately redefined in subclass. For example, Range#=== returns true when argument is within the range.

Therefore, It is marked as unsafe by default because === and == do not always behave the same.

# bad
items.all? { |item| pattern === item }
items.all? { |item| item == other }
items.all? { |item| item.is_a?(Klass) }
items.all? { |item| item.kind_of?(Klass) }

# good
items.all?(pattern)

cf. rails/rails#41363

Thank you for the cop idea @kamipo!

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