Create link-check.yml (#853)

* Create link-check.yml

* Update link-check.yml

.github/workflows/link-check.yml

+name: 'Link check'
+
+on:
+  schedule:
+    # check links at 01:30 a.m. every day
+    - cron: '30 1 * * *'
+
+jobs:
+  link-check:
+    runs-on: ubuntu-latest
+    steps:
+      # - uses: actions/checkout@v3
+
+      - name: linkchecker
+        run: |
+          pip install linkchecker
+          linkchecker https://opencompass.readthedocs.io/ --no-robots -t 30