feat(config.yml): Hello CircleCI

I added a new folder(.circleci) with a new file (config.yml) inside.
I wrote a hello world code in the config.yml

.circleci/config.yml

@@ -0,0 +1,13 @@
+version: 2.1
+workflows:
+    version: 2.1
+    build_and_test:
+      jobs:
+        - build
+jobs:
+  build:
+    docker: 
+      - image: cimg/node:14.10.1 # the primary container, where your job's commands are run
+    steps:
+      - checkout # check out the code in the project directory
+      - run: echo "hello world" # run the `echo` command