Lowercase keys and reduce logic

danger/roulette/Dangerfile

@@ -97,7 +97,7 @@ categories = Set.new(changes.keys - [:unknown])
 categories << :database if helper.mr_labels.include?('database')
 
 # Ensure to spin for UX reviewer for community contributions when ~UX is applied (e.g. to review changes to the UI)
-categories << :UX if helper.mr_labels.include?('UX') && helper.mr_labels.include?('Community contribution')
+categories << :ux if (["UX", "Community contribution"] - helper.mr_labels).empty?
 
 # Ensure to spin for Product Intelligence reviewer when ~"product intelligence::review pending" is applied
 categories << :product_intelligence if helper.mr_labels.include?("product intelligence::review pending")

danger/specialization_labels/Dangerfile

@@ -6,7 +6,7 @@ SPECIALIZATIONS = {
   database: 'database',
   backend: 'backend',
   frontend: 'frontend',
-  UX: 'UX',
+  ux: 'UX',
   docs: 'documentation',
   qa: 'QA',
   tooling: 'type::tooling',