Run GitHub CI on at least Node 20

Author: rubensworks

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
           key: ${{ runner.os }}-lint-modules-${{ hashFiles('**/yarn.lock') }}
       - uses: actions/setup-node@v4
         with:
-          node-version: 18.x
+          node-version: 20.x
       - run: yarn install
       - run: yarn run lint
 
@@ -22,7 +22,6 @@ jobs:
       matrix:
         os: [ubuntu-latest]
         node-version:
-          - 18.x
           - 20.x
           - 22.x
           - 24.x