Drop support for React before v16.8

Hooks did not exist before this version.

Author: jakezatecky

CHANGELOG.md

@@ -25,6 +25,10 @@
 * The `rct-options` and `rct-option` CSS classes are now `rct-actions` and `rct-action` respectively
 * The `rct-title` CSS class is now `rct-label`
 
+#### Other
+
+* Drop support for React before v16.8
+
 ### New Features
 
 * Add `checkKeys` property to allow specification of JavaScript keys to trigger check behavior

package.json

@@ -40,7 +40,7 @@
     "test:style-format": "prettier --check src/scss/**/*.scss examples/src/scss/**/*.scss"
   },
   "peerDependencies": {
-    "react": "^15.3.0 || ^16.0.0 || ^17.0.0 || ^18.0.0"
+    "react": "^16.8.0 || ^17.0.0 || ^18.0.0"
   },
   "devDependencies": {
     "@babel/core": "^7.0.0",