dependency: bump puma from 5.2.1 to 5.2.2

Bumps puma from 5.2.1 to 5.2.2.

Changelog

Sourced from puma's changelog.

5.2.2 / 2021-02-22

• Bugfixes
  • Add #flush and #sync methods to Puma::NullIO (#2553)
  • Restore sync=true on STDOUT and STDERR streams (#2557)

Commits

• a192434 Fix CI (#2561)
• 7970d14 5.2.2 [ci skip]
• 7a2cdf6 Restore sync=true on global stdout/stderr streams (#2557)
• 1555ca2 .rubocop.yml - exclude local bundles in test/worker_gem_independence_test
• b0bd212 Update check_changelog.yml
• 7c91d90 Add #flush and #sync methods to Puma::NullIO (#2553)
• 26776c8 GitHub Actions now supports skipping tests
• 56512ba Update architecture.md
• See full diff in compare view