Skip link-check on "SECURITY.md"

Author: atifaziz

.github/workflows/markdown-ci.yml

@@ -23,4 +23,6 @@ jobs:
     - uses: actions/checkout@v2
     - run: |
         npm install -g [email protected]
-        git ls-files -z '*.md' | xargs -0 -n1 markdown-link-check --config .markdownlinkcheck.jsonc
+        git ls-files '*.md' \
+        | grep -vE '^SECURITY\.md$' \
+        | xargs -n1 markdown-link-check --config .markdownlinkcheck.jsonc