bump parallelism to 12

Author: antoinerg

.circleci/config.yml

@@ -113,7 +113,7 @@ jobs:
   test-image-orca:
     docker:
       - image: antoinerg/orca-reproducible:latest
-    parallelism: 8
+    parallelism: 12
     working_directory: ~/plotly.js
     steps:
       - checkout