ci(travis): update caching syntax

curbengh · curbengh · commit ceb046caa33c · 2019-12-10T00:19:10.000Z
diff --git a/.travis.yml b/.travis.yml
@@ -5,9 +5,7 @@ os:
 language: node_js
 
 cache:
-  apt: true
-  directories:
-    - node_modules
+  npm: true
 
 node_js:
   - "8"
