Support and test only Node.js >=22.x.

Author: davidlehn

.github/workflows/main.yaml

@@ -46,7 +46,7 @@ jobs:
     timeout-minutes: 10
     strategy:
       matrix:
-        node-version: [20.x, 22.x, 24.x]
+        node-version: [22.x, 24.x]
     steps:
       - uses: actions/checkout@v6
         with: