[Docs] Supplement volunteers and faq docs (#182)

Signed-off-by: Gaohan123 <hgaoaf@connect.ust.hk>

docs/mkdocs/stylesheets/extra.css

@@ -25,8 +25,11 @@ a:not(:has(svg)):not(.md-icon):not(.autorefs-external) {
 
 a[href*="localhost"]::after,
 a[href*="127.0.0.1"]::after,
-a[href*="org.readthedocs.build"]::after,
-a[href*="docs.vllm.ai"]::after {
+
+/* Hide external link icons for all links */
+a[href^="//"]::after,
+a[href^="http://"]::after,
+a[href^="https://"]::after {
     display: none !important;
 }