Add documentation linter to validate links

Author: Cecile Robert-Michon

.github/workflows/lint-docs.yaml

@@ -0,0 +1,21 @@
+name: Check Markdown links
+
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - '**.md'
+  pull_request:
+    paths:
+      - '**.md'
+
+jobs:
+  markdown-link-check:
+    name: Broken Links
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - uses: gaurav-nelson/github-action-markdown-link-check@v1
+      with:
+        config-file: .markdownlinkcheck.json

.markdownlinkcheck.json

@@ -0,0 +1,12 @@
+{
+    "ignorePatterns": [
+        {
+        "pattern": "^http://localhost"
+        }
+],
+    "timeout": "5s",
+    "retryOn429": true,
+    "retryCount": 5,
+    "fallbackRetryDelay": "30s",
+    "aliveStatusCodes": [200, 206]
+}