chore: Ignore broken doc links we can't fix

Author: LukeMathWalker

.github/ci_generator/templates/job_steps/build_docs.jinja

@@ -41,8 +41,10 @@
       --exclude-path="site/api_reference/settings.html"
       --exclude-path="site/404.html"
       --exclude=".*crate#per-style$"
+      --exclude=".*#setting-the-default-subscriber$"
       --exclude="https://doc.rust-lang.org/*"
       --exclude="https://stackoverflow.com/*"
+      --exclude="https://rust-random.github.io/*"
       --exclude="https://github.com/LukeMathWalker/pavex/edit/main/*"
       --exclude="https://docs.rs/**/*"
       --exclude-path="site/api_reference/static.files"