v2.18.1

This is a hotfix release that addresses a CSS color issue with SVG icons on light themes in Microsoft Edge 18.

Bug Fixes 🐛

• fix: Correct icon color rules #1752 (@remydenton @sghoweri)

Misc 🔧

• [skip travis] chore(release): release v2.18.1 (@bolt-bot)
• [skip travis] chore: version bump PHP-related dependencies to v2.18.1 (@bolt-bot)

Authors: 3

• Bolt Bot (@bolt-bot)
• Rémy Denton (@remydenton)
• Salem Ghoweri (@sghoweri)