ruby: repeated_field aliases each_index to each_with_index - thus incorrectly returning the each not the index

[jufemaiz]

Aliased method for each_index is invalid:

protobuf/ruby/lib/google/protobuf/repeated_field.rb

Lines 106 to 110 in 63d2f3b

	# array aliases into enumerable
	alias_method :each_index, :each_with_index
	alias_method :slice, :[]
	alias_method :values_at, :select
	alias_method :map, :collect

Ref:

• array: https://ruby-doc.org/core-2.7.1/Array.html#method-i-each_index
• enumerable: https://ruby-doc.org/core-2.7.1/Enumerable.html#method-i-each_with_index

What version of protobuf and what language are you using?
Version: master
Language: ruby

What operating system (Linux, Windows, ...) and version?

Docker: ruby:2.7-slim-buster

What runtime / compiler are you using (e.g., python version or gcc version)

N/A

What did you do?
Steps to reproduce the behavior:

1. have a proto with a repeated_field
2. build a ruby library
3. make use of each_index

What did you expect to see

The index of the repeated field.

What did you see instead?

The repeated field's value instead.

Make sure you include information that can help us debug (full error message, exception listing, stack trace, logs).

Anything else we should know about your project / environment

N/A