Roo bug: floating-point values in "0%"-formatted cells are truncated instead of rounded by :formatted_value

percentage_float_test.xlsx

test_incorrect_percentage_rounding.rb

# frozen_string_literal: true

require 'bundler/inline'

gemfile(true) do
  source 'https://rubygems.org'

  git_source(:github) { |repo| "https://github.com/#{repo}.git" }

  gem 'minitest'
  gem 'roo'
end

require 'minitest/autorun'
require 'roo'

class PercentageFloatRoundingTest < Minitest::Test
  def test_cell_value_rounds_percentage_formatted_value
    spreadsheet = Roo::Spreadsheet.open("percentage_float_test.xlsx")
    cell        = spreadsheet.sheet_for('Sheet1').cells[[1, 1]]
    assert_equal '57%', cell.formatted_value
  end
end

Steps to reproduce

Download spreadsheet and script above and run; you may need to modify the file path on line 19.

Expected behavior

Test should pass. The spreadsheet contains a single cell with the value 57% as a 0%-formatted percentage. :formatted_value should return "57%".

Actual behavior

:formatted_value returns 56%.

PR incoming!