Bump parallel_tests from 2.21.1 to 2.21.2#3872

dependabot-preview[bot] wants to merge 1 commit intomasteralphagov/whitehall:masterfrom

dependabot/bundler/parallel_tests-2.21.2alphagov/whitehall:dependabot/bundler/parallel_tests-2.21.2Copy head branch name to clipboard