In 5.5, gh-samples-url points to https://github.com/spring-projects/spring-security/tree/5.5.0/samples, but the samples have moved to spring-security-samples, so the links are broken.
For links that point to samples that have not yet been migrated, the link should be removed and a ticket should be added to spring-security-samples to ensure that the sample gets migrated.
Since this first released in 5.5, these links should be backported to the 5.5 documentation as well.
Comment From: marcusdacoregio
Created ticket https://github.com/spring-projects/spring-security-samples/issues/22 to map not migrated samples.
Closing as this issue was solved in https://github.com/spring-projects/spring-security/pull/9826/commits/53310998f5961bd65a46f864c8d3b7f4ccba705e