fix(manifest.json): update icon19 and icon38

Author: vincentha766

image/icon/default/icon19.png

@@ -30,8 +30,8 @@
     ],
     "browser_action": {
         "default_icon": {
-            "19": "image/icon/default/icon64.png",
-            "38": "image/icon/default/icon64.png"
+            "19": "image/icon/default/icon19.png",
+            "38": "image/icon/default/icon38.png"
         },
         "default_title": "Cloudopt AdBlocker",
         "default_popup": "popup.html"