Wrong detection and harmful autofix to RuboCop::Cop::Style::HashTransformValues

[Bartuz]

Current docs for HashTransformValues mentions that

# bad
{a: 1, b: 2}.each_with_object({}) { |(k, v), h| h[k] = foo(v) }
Hash[{a: 1, b: 2}.collect { |k, v| [k, foo(v)] }]
{a: 1, b: 2}.map { |k, v| [k, v * v] }.to_h
{a: 1, b: 2}.to_h { |k, v| [k, v * v] }

# good
{a: 1, b: 2}.transform_values { |v| foo(v) }
{a: 1, b: 2}.transform_values { |v| v * v }

It isn't included, but it would also complain for this code: {a: 1, b: 2}.to_h { |k, _unused_v| [k, k] }
Notice: value of the hash is not used at all. It's just using key

There are two issues with that:

1. It shouldn't complain when value is not used at all (as it recommends to use transform_values, which in that case is not possible to be used)
2. Autocorrects to code with NameError: undefined local variable or method 'k' for main:Object

Example code in "Steps to reproduce" section

---

Expected behavior

Two possible fixes:

1. Shouldn't detect HashTransformValues rule when .to_h { |k, v| ... } is not using value v.
2. Shouldn't autofix (-A) to code with NameError (don't correct it for the user, let user fix the issue themselves?)

Actual behavior

Detects offence and autofixes to code which raises NameError.

Steps to reproduce the problem

hash = {
  a: { value: 2 },
  b: { value: 3 }
}

# expected result: { a: :a, b: :b }
# rubocop complains about the line below
hash.to_h { |k, _v| [k, k] }

# rubocop -A output.
# this code causes NameError (undefined k)
hash.transform_values { |_v| k }

# rubocop -A output below
#
# try.rb:7:1: C: [Corrected] Style/HashTransformValues: Prefer transform_values over to_h {...}.
#   hash.to_h { |k, _v| [k, k] }
# ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
#  
#
#  1 file inspected, 1 offenses detected, 1 offenses corrected

RuboCop version

rubocop -V
1.35.0 (using Parser 3.1.2.1, rubocop-ast 1.21.0, running on ruby 3.1.0 x86_64-darwin21)
  - rubocop-performance 1.14.2
  - rubocop-rails 2.15.1