Update node.js on Travis CI from v8 to v18

PeterDaveHello · PeterDaveHello · commit 275bae5f45b7 · 2022-06-04T16:35:54.000+08:00
diff --git a/.travis.yml b/.travis.yml
@@ -23,7 +23,7 @@ jobs:
         - Test: dockerfile_lint
       language: node_js
       node_js:
-        - "8"
+        - "18"
       script:
         - npx --cache .npx dockerfile_lint
       cache:
