CI: Remove workaround for mdBook issue

rust-lang/mdBook#789 has been fixed and this was working locally without
the `ignore-url`.

Author: phansch

ci/script.sh

@@ -4,15 +4,13 @@ main() {
     mdbook build
     mdbook test
 
-    # FIXME(rust-lang/mdbook#789) remove `--ignore-url` when that bug is fixed
-    linkchecker --ignore-url "print.html" book
+    linkchecker book
 
     # now check this as a directory of the bookshelf
     rm -rf shelf
     mkdir shelf
     mv book shelf
-    # FIXME(rust-lang/mdbook#789) remove `--ignore-url` when that bug is fixed
-    linkchecker --ignore-url "print.html" shelf
+    linkchecker shelf
 
     mv shelf/book .
     rmdir shelf