Fix sanitization for array case - was missing a return value (#3199)

(cherry picked from commit c05ae111d0)

InvenTree/InvenTree/static/script/inventree/inventree.js

@@ -287,10 +287,12 @@ function sanitizeData(data) {
         return null;
     } else if (Array.isArray(data)) {
         // Handle arrays
-        var ret = [];
+        var arr = [];
         data.forEach(function(val) {
-            ret.push(sanitizeData(val));
+            arr.push(sanitizeData(val));
         });
+
+        return arr;
     } else if (typeof(data) === 'object') {
         // Handle nested structures
         var nested = {};