Add workflow (#26)

Author: Tahanima

.github/workflows/action.yml

@@ -0,0 +1,16 @@
+name: Check Markdown links
+
+on:
+  push:
+    branches: [ main ]
+    paths:
+      - '**.md'
+  pull_request:
+    paths:
+      - '**.md'
+jobs:
+  markdown-link-check:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - uses: gaurav-nelson/github-action-markdown-link-check@v1