Fix broken links in the docs

data/deprecations/15-6-deprecate-runner-register-command.yml

...ons/15-6-deprecate-runner-register-token-k8s-operator.yml

doc/administration/auth/ldap/index.md

doc/administration/redis/replication_and_failover.md

doc/development/ai_architecture.md

doc/development/secure_coding_guidelines.md

doc/development/testing_guide/best_practices.md

doc/update/deprecations.md