Rubocop reports only the first of multiple Style/CommentAnnotation offenses if they are not separated by another line.

Gemfile

# frozen_string_literal: true

source 'https://rubygems.org'

ruby '2.5.0'

gem 'rubocop'

Gemfile.lock

GEM
  remote: https://rubygems.org/
  specs:
    ast (2.4.0)
    parallel (1.12.1)
    parser (2.5.0.4)
      ast (~> 2.4.0)
    powerpack (0.1.1)
    rainbow (3.0.0)
    rubocop (0.54.0)
      parallel (~> 1.10)
      parser (>= 2.5)
      powerpack (~> 0.1)
      rainbow (>= 2.2.2, < 4.0)
      ruby-progressbar (~> 1.7)
      unicode-display_width (~> 1.0, >= 1.0.1)
    ruby-progressbar (1.9.0)
    unicode-display_width (1.3.0)

PLATFORMS
  ruby

DEPENDENCIES
  rubocop

RUBY VERSION
   ruby 2.5.0p0

BUNDLED WITH
   1.16.1

rubocop_output.txt

jandavid@STS ~/D/j/rubocop-todo-bug> rubocop
Inspecting 2 files
C.

Offenses:

todo.rb:5:11: C: Style/CommentAnnotation: Annotation keywords like TODO should be all upper case, followed by a colon, and a space, then a note describing the problem.
    '', # TODO Item 1
          ^^^^^
todo.rb:8:11: C: Style/CommentAnnotation: Annotation keywords like TODO should be all upper case, followed by a colon, and a space, then a note describing the problem.
    '', # TODO Item 3
          ^^^^^

2 files inspected, 2 offenses detected

todo.rb

# frozen_string_literal: true

class ToBeDone
  ITEMS = [
    '', # TODO Item 1
    '', # TODO Item 2

    '', # TODO Item 3
  ].freeze
end