JIRA: https://jira.spring.io/browse/INT-4484 Fix the `SyndEntryPublishedDateComparator` to move entries without a date into the end of the sorted list **Cherry-pick to 5.0.x and 4.3.x**
JIRA: https://jira.spring.io/browse/INT-4484 Fix the `SyndEntryPublishedDateComparator` to move entries without a date into the end of the sorted list **Cherry-pick to 5.0.x and 4.3.x**