chore: update HTML verification workflow and add configuration file (#477)

On-behalf-of: Gerald Morrison (SAP) <[email protected]>

<!-- markdownlint-disable MD041 -->
#### What this PR does / why we need it
Use new HTML (link) checker. It checks internal and external links.

## What issue is fixed?
fixes open-component-model/ocm-project/issues/498

Signed-off-by: Gerald Morrison (SAP) <[email protected]>
Co-authored-by: Gerald Morrison (SAP) <[email protected]>

Author: morri-son

.github/config/htmltest.yml

@@ -0,0 +1,31 @@
+# HTMLTest option reference: https://github.com/wjdp/htmltest?tab=readme-ov-file#basic-options
+
+# Directory for HTMLTest to scan
+DirectoryPath: ./public
+
+# Checks to ignore
+CheckInternalHash: false
+CheckDoctype: false
+IgnoreInternalEmptyHash: true
+IgnoreAltMissing: true
+IgnoreEmptyHref: true
+IgnoreDirectoryMissingTrailingSlash: true
+
+# Avoid HTTP 403 Errors (on corporate pages): Override User-Agent and referer
+HTTPHeaders:
+  "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36"
+  "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8"
+  "Accept-Language": "en-US,en;q=0.9"
+  "Referer": "https://ocm.software"
+ExternalTimeout: 10
+
+# URLs to ignore
+IgnoreURLs:
+  # Skip all SAP legal pages (appears in footer, so on every page)
+  - "^https://www\\.sap\\.com/.*/legal/.*"
+  - "^mailto:"
+  # Skip local pages from secure delivery demo
+  - "^https?://(www\\.)?gitea\\.ocm\\.dev(/|$)"
+  - "^https://.*\\.ocm\\.dev(/|$)"
+  # Skip Google calendar entries
+  - "^https://calendar\\.google\\.com(/|$)"

.github/workflows/verify-html.yml

@@ -1,4 +1,7 @@
-name: Verify HTML
+# This workflow verifies that all links in the HTML files are valid.
+# GitHub repo: https://github.com/wjdp/htmltest
+
+name: Verify HTML Links
 
 on:
   pull_request:
@@ -10,19 +13,25 @@ permissions:
 
 jobs:
   check-links:
-    name: Check links
+    name: Check external and internal links
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+
       - name: Setup Node.js
         uses: actions/setup-node@v4
         with:
           node-version: 22.12.0 # keep in sync with 'engines'@package.json
+
       - name: Install Dependencies
         run: npm install
+
       - name: Build Site
         run: npm run build
+
       - name: Verify HTML links
-        uses: untitaker/[email protected]
-        with:
-          args: public/ --sources content/
+        # Download binary to ./bin. Execute it with log level 1 (INFO) and config file
+        run: |
+          curl https://htmltest.wjdp.uk | bash
+          chmod +x ./bin/htmltest
+          ./bin/htmltest -l 1 -c .github/config/htmltest.yml