message: Add yarn as first step of each CI step
diff: @@ -24,6 +24,7 @@ jobs:
  - name: test
  run: |
  set -ex
  + yarn
  npx ts-mocha -r tsconfig-paths/register ./test/*.ts
  yarn run tslint
  yarn run prettier
  @@ -34,5 +35,6 @@ jobs:
  - name: build and deploy
  run: |
  set -ex
  + yarn
  yarn run build
  yarn run typedoc
  