Update .travis.yml

Author: chcost

.travis.yml

@@ -18,14 +18,14 @@ language: python
 python:
   - "3.8"
 
- cache:
-    directories:
-     - ./resources/data
-
 install:
   - pip install -r requirements.txt
   - pip install ray[default]
   - pip install .
 
+cache:
+  directories:
+    - ./resources/data
+
 script:
   - pytest