Support React 18 as a peer dependency

.babelrc

@@ -4,6 +4,6 @@
     "@babel/preset-react"
   ],
   "plugins": [
-    "transform-object-assign"
+    "@babel/plugin-transform-object-assign"
   ]
 }

.github/workflows/test.yml

@@ -0,0 +1,20 @@
+name: Checks + Tests
+on: [push, pull_request]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v4
+    - name: Use Node.js
+      uses: actions/setup-node@v4
+      with:
+        node-version: '20.x'
+        cache: 'npm'
+    - name: NPM install
+      run: npm install
+    - name: Verify build works
+      run: npm run build
+    - name: Jest
+      run: npm run test
+

README.md

@@ -1,6 +1,3 @@
-[![Build Status](https://img.shields.io/travis/scniro/react-codemirror2.svg?style=flat-square)](https://travis-ci.org/scniro/react-codemirror2)
-[![Dependency Status](https://img.shields.io/david/scniro/react-codemirror2.svg?label=deps&style=flat-square)](https://david-dm.org/scniro/react-codemirror2)
-[![DevDependency Status](https://img.shields.io/david/dev/scniro/react-codemirror2.svg?label=devDeps&style=flat-square)](https://david-dm.org/scniro/react-codemirror2#info=devDependencies)
 [![Coverage](https://img.shields.io/coveralls/scniro/react-codemirror2.svg?style=flat-square)](https://coveralls.io/github/scniro/react-codemirror2)
 [![Downloads](https://img.shields.io/npm/dm/react-codemirror2.svg?style=flat-square)](https://www.npmjs.com/package/react-codemirror2)
 [![NPM Version](https://img.shields.io/npm/v/react-codemirror2.svg?style=flat-square)](https://www.npmjs.com/package/react-codemirror2)