Check for broken links (#1422)

Co-authored-by: Joris LIMONIER <joris.limonier@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

.github/workflows/links.yml

@@ -0,0 +1,38 @@
+# Ultralytics YOLO 🚀, GPL-3.0 license
+# YOLO Continuous Integration (CI) GitHub Actions tests
+
+name: Check Broken links
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+  workflow_dispatch:
+  schedule:
+    - cron: '0 0 * * *'  # runs at 00:00 UTC every day
+
+jobs:
+  Links:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Test Markdown and HTML links
+        uses: lycheeverse/lychee-action@v1.6.1
+        with:
+          fail: true
+          # accept 429(Instagram, 'too many requests'), 999(LinkedIn, 'unknown status code'), Timeout(Twitter)
+          args: --accept 429,999 --exclude twitter.com --verbose --no-progress './**/*.md' './**/*.html'
+        env:
+          GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}
+
+      - name: Test Markdown, HTML, YAML, Python and Notebook links
+        if: github.event_name == 'workflow_dispatch'
+        uses: lycheeverse/lychee-action@v1.6.1
+        with:
+          fail: true
+          # accept 429(Instagram, 'too many requests'), 999(LinkedIn, 'unknown status code'), Timeout(Twitter)
+          args: --accept 429,999 --exclude twitter.com,url.com --verbose --no-progress './**/*.md' './**/*.html' './**/*.yml' './**/*.yaml' './**/*.py' './**/*.ipynb'
+        env:
+          GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}