Fix trailing whitespace

doc/administration/postgresql/replication_and_failover.md

doc/architecture/blueprints/activity_pub/index.md

doc/architecture/blueprints/capacity_planning/index.md

doc/architecture/blueprints/cells/index.md

...ecture/blueprints/modular_monolith/packages_extraction.md

doc/development/build_test_package.md

doc/update/versions/gitlab_16_changes.md

.../application_security/policies/scan-execution-policies.md

doc/user/group/custom_project_templates.md

doc/user/group/saml_sso/group_sync.md

doc/user/profile/account/two_factor_authentication.md