Add missing dictionary files

What does this MR do and why?

We are missing a few entries in /db/docs/. Those entries are present in gitlab_schemas.yml. To find the missing entries, I have used the following script:

GITLAB_SCHEMAS_FILE = 'lib/gitlab/database/gitlab_schemas.yml'
tables_to_schema ||= YAML.load_file(Rails.root.join(GITLAB_SCHEMAS_FILE))
DIRECTORY_PATH = '/Users/diogo/gitlab-development-kit/gitlab/db/docs/'

tables_to_schema.each do |table_name, gitlab_schema|
  file_path = DIRECTORY_PATH.to_s+table_name+".yml"

  unless File.file?(file_path)
    content = { "gitlab_schema" => gitlab_schema.to_s }
    File.open("#{DIRECTORY_PATH}#{table_name}.yml", "w") { |file| file.write(content.to_yaml) }
  end
end

gitlab-org/database-team/team-tasks#260 (closed)

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