Drop Node 14 from CI, add Node 20

Author: ericyhwang

.github/workflows/test.yml

@@ -15,9 +15,9 @@ jobs:
     strategy:
       matrix:
         node:
-        - 14
         - 16
         - 18
+        - 20
     services:
       redis:
         image: redis

package.json

@@ -5,7 +5,7 @@
   "main": "index.js",
   "dependencies": {
     "redis": "^2.6.0 || ^3.0.0",
-    "sharedb": "^1.0.0 || ^2.0.0 || ^3.0.0"
+    "sharedb": "^1.0.0 || ^2.0.0 || ^3.0.0 || ^4.0.0"
   },
   "devDependencies": {
     "chai": "^4.2.0",