check for 404s and 500s on previews (#601)

* chore: add shared security responsibility doc

* add docs 404 check

* install dependencies

* Revert "Merge remote-tracking branch 'origin/katiehorne/ch14532' into bpmct/detect-docs-404"

This reverts commit 9cecf22, reversing
changes made to 532c1b8.

Co-authored-by: Katie Horne <katie@coder.com>

Author: bpmct

.github/workflows/preview.yaml

@@ -61,6 +61,16 @@ jobs:
           VERCEL_TOKEN: ${{ secrets.VERCEL_TOKEN }}
           CODER_DOCS_MAIN_BRANCH: ${{ github.event.pull_request.head.sha }}
 
+      # This ensures the docs site is built properly
+      # as it will sometimes throw a 404 or 500
+      # error if Markdown/parsing errors are present
+      - name: Install node_modules
+        run: yarn install
+      - name: Check docs
+        run: yarn ts-node ./product/coder.com/site/scripts/checkDocs.ts
+        env:
+          BASE_URL: ${{ steps.preview.outputs.url }}
+
       - name: Update Deployment
         # If we don't specify always, it won't run this check if failed.
         # This means the deployment would be stuck pending.