http: replace var with let

PR-URL: #30421 Reviewed-By: James M Snell <[email protected]> Reviewed-By: Anna Henningsen <[email protected]> Reviewed-By: Michaël Zasso <[email protected]> Reviewed-By: Colin Ihrig <[email protected]> Reviewed-By: David Carlier <[email protected]> Reviewed-By: Gireesh Punathil <[email protected]> Reviewed-By: Ruben Bridgewater <[email protected]> Reviewed-By: Trivikram Kamat <[email protected]>

Author: Guilherme Goncalves

lib/internal/http.js

@@ -3,8 +3,8 @@
 const{ setUnrefTimeout }=require('internal/timers');
 const{ PerformanceEntry, notify }=internalBinding('performance');
 
-varnowCache;
-varutcCache;
+letnowCache;
+letutcCache;
 
 functionnowDate(){
 if(!nowCache)cache();