Remove unused CI configs

.circleci/config.yml

@@ -1,17 +0,0 @@
-version: 2.1
-orbs:
-  node: circleci/node@1.1.6
-jobs:
-  build-and-test:
-    executor:
-      name: node/default
-    steps:
-      - checkout
-      - node/with-cache:
-          steps:
-            - run: npm install
-            - run: npm test
-workflows:
-    build-and-test:
-      jobs:
-        - build-and-test

.travis.yml

@@ -1,12 +0,0 @@
-language: node_js
-node_js:
-  - '10'
-  - '12'
-
-cache:
-  directories:
-    - $HOME/.cache/yarn
-
-script:
-  - yarn
-  - yarn run test