chore(gitlab-ci): better caching

.gitlab-ci.yml

@@ -1,7 +1,7 @@
 default:
   image:
     name: fpco/stack-build:lts-16.11
-  cache:
+  cache: &global_cache
     paths:
       - node_modules
       - .stack
@@ -57,6 +57,9 @@ npm install:
   interruptible: true
   
 frontend:build:
+  cache:
+    <<: *global_cache
+    policy: pull
   stage: frontend:build
   script:
     - npm run frontend:build
@@ -146,6 +149,9 @@ yesod:build:
   resource_group: ram
 
 frontend:test:
+  cache:
+    <<: *global_cache
+    policy: pull
   stage: test
   script:
     - npm run frontend:test
@@ -167,6 +173,7 @@ frontend:test:
   interruptible: true
 
 deploy:uniworx3:
+  cache: {}
   stage: deploy
   script:
     - zip -qj - bin/uniworx bin/uniworxdb | ssh root@uniworx3.ifi.lmu.de /root/bin/accept_uni2work