fix(serializer): switch let to var

Author: digitalsadhu

lib/serializer.js

@@ -380,18 +380,18 @@ function handleIncludes (resp, includes, relations, app) {
 
   if (embedded.length) {
     // This array may contain duplicate models if the same item is referenced multiple times in 'data'
-    let duplicate = _.flattenDeep(embedded)
+    var duplicate = _.flattenDeep(embedded)
     // So begin with an empty array that will only contain unique items
-    let unique = []
+    var unique = []
     // Iterate through each item in the first array
-    duplicate.forEach(function(d){
+    duplicate.forEach(function (d) {
       // Count the number of items in the unique array with matching 'type' AND 'id'
       // Since we're adhering to the JSONAPI spec, both 'type' and 'id' can assumed to be present
       // Both 'type' and 'id' are needed for comparison because we could theoretically have objects of different
       // types who happen to have the same 'id', and those would not be considered duplicates
-      let count = unique.filter(function(u){
+      var count = unique.filter(function (u) {
         return (u.type === d.type) && (u.id === d.id)
-      }).length;
+      }).length
       // If there are no matching entries, then add the item to the unique array
       if (count === 0) {
         unique.push(d)