Why am I seen 404 not found when adding https://artifacts.elastic.co/packages/6.x/yum/ as remote rpm repository?

AuthorFullName__c
Batel Tova
articleNumber
000004231
ft:sourceType
Salesforce
FirstPublishedDate
2018-11-14T14:13:27Z
lastModifiedDate
2018-11-14
VersionNumber
4