chore: Specify v8 as the node version

achingbrain · daviddias · commit 7a027ccdd4c4 · 2018-05-06T15:53:16.000+02:00
diff --git a/circle.yml b/circle.yml
@@ -1,7 +1,7 @@
 # Warning: This file is automatically synced from https://github.com/ipfs/ci-sync so if you want to change it, please change it there and ask someone to sync all repositories.
 machine:
   node:
-    version: carbon
+    version: 8
 
 test:
   pre:
