v2.15.18 Dependency updates

What's Changed

• Update dependencies by @jazairi in #1088
• Update scout_apm: 5.3.2 → 5.3.3 (patch) by @depfu in #1089
• Update sentry-rails: 5.6.0 → 5.7.0 (minor) by @depfu in #1090
• Update net-imap: 0.3.1 → 0.3.2 (minor) by @depfu in #1092
• Update selenium-webdriver: 4.6.1 → 4.7.1 (minor) by @depfu in #1091

Full Changelog: v2.5.17...v2.5.18