Correct validation backlog label name in issue template

.gitlab/issue_templates/Problem_Validation.md

@@ -38,4 +38,4 @@
 
 For example, if the solution will take a product manager, designer, and engineer two weeks of effort - you may quantify this as 1.5 (based on 0.5 months x 3 people). -->
 
-/label ~"workflow::problem backlog"
+/label ~"workflow::validation backlog" ~devops:: ~category: ~group::