add default cache (#8120)

circle.yml

@@ -87,6 +87,25 @@ jobs:
         - ~/.stack
         - /home/circleci/OpenAPITools/openapi-generator/samples/client/petstore/haskell-http-client/.stack-work
         - ~/R
+    # save "default" cache using the key "source-v2-"
+    - save_cache:
+        key: source-v2-
+        paths:
+        # This is a broad list of cache paths to include many possible development environments
+        # You can probably delete some of these entries
+        - vendor/bundle
+        - ~/virtualenvs
+        - ~/.m2
+        - ~/.ivy2
+        - ~/.sbt
+        - ~/.bundle
+        - ~/.go_workspace
+        - ~/.gradle
+        - ~/.cache/bower
+        - ".git"
+        - ~/.stack
+        - /home/circleci/OpenAPITools/openapi-generator/samples/client/petstore/haskell-http-client/.stack-work
+        - ~/R
     # Teardown
     #   If you break your build into multiple jobs with workflows, you will probably want to do the parts of this that are relevant in each
     # Save test results