chore(utils): Move generic utils from region module to utils (#6466)

Moves some generic utilities from the region module to the top-level utils package

packages/utils/src/common/get-duplicates.ts

@@ -0,0 +1,16 @@
+// This function is intentionally not generic, as we will likely need a comparator function in that case, which will make it more complex than necessary
+// Revisit if there is such use-case in the future
+export const getDuplicates = (collection: string[]): string[] => {
+  const uniqueElements = new Set<string>()
+  const duplicates = new Set<string>()
+
+  collection.forEach((item) => {
+    if (uniqueElements.has(item)) {
+      duplicates.add(item)
+    } else {
+      uniqueElements.add(item)
+    }
+  })
+
+  return Array.from(duplicates)
+}