CI: separate node10 and 12 cache (#1527)

Previously both node versions would share the same cache.
This caused one of the two versions to always rebuild
the `better-sqlite3` package, costing about 1 min per job.

Now we're using a different cache key for each version,
rebuilding a cached `better-sqlite3` should no longer be
necessary.

.circleci/config.yml

@@ -22,17 +22,22 @@ executors:
 commands:
   set_up_node_modules:
     description: "load node_modules, updating and storing back into cache if necessary"
+    parameters:
+      node_version:
+        description: Which node version we're caching packages for
+        type: integer
+        default: 12
     steps:
       - restore_cache:
           keys:
-            - v1-dependencies-{{ checksum "package.json" }}
+            - v1-node<< parameters.node_version >>-dependencies-{{ checksum "package.json" }}
             # fall back to using the latest cache if no exact match is found
-            - v1-dependencies-
+            - v1-node<< parameters.node_version >>-dependencies-
       - run: yarn install
       - save_cache:
           paths:
             - node_modules
-          key: v1-dependencies-{{ checksum "package.json" }}
+          key: v1-node<< parameters.node_version >>-dependencies-{{ checksum "package.json" }}
   pull_cache:
     description: Pulls docker images usable for our cache
     steps:
@@ -56,7 +61,8 @@ jobs:
     executor: node10
     steps:
       - checkout
-      - set_up_node_modules
+      - set_up_node_modules:
+          node_version: 10
       - run: yarn test --full --ci
 
 workflows: