ci(travis.cache): change syntax of travis cache to fix build issues

Tbhesswebber · Tbhesswebber · commit 0408315e248f · 2019-02-17T06:29:04.000-05:00
Regularly fails while reaching into cache for pack.js
diff --git a/.travis.yml b/.travis.yml
@@ -1,8 +1,6 @@
 sudo: false
 language: node_js
-cache:
-  directories:
-    - node_modules
+cache: npm
 node_js:
   - 8
   - 10
