Updated config json to add exercise to track.

Author: BethanyG

config.json

@@ -981,24 +981,6 @@
         ],
         "difficulty": 3
       },
-      {
-        "slug": "swift-scheduling",
-        "name": "Swift Scheduling",
-        "uuid": "ebddfc37-a3fc-4524-bd62-9c70f979713c",
-        "practices": [],
-        "prerequisites": ["basics",
-          "bools",
-          "conditionals",
-          "lists",
-          "list-methods",
-          "loops",
-          "numbers",
-          "strings",
-          "string-methods"
-        ],
-        "difficulty": 3,
-        "status": "wip"
-      },
       {
         "slug": "ocr-numbers",
         "name": "OCR Numbers",
@@ -1345,6 +1327,23 @@
         ],
         "difficulty": 4
       },
+      {
+        "slug": "swift-scheduling",
+        "name": "Swift Scheduling",
+        "uuid": "ebddfc37-a3fc-4524-bd62-9c70f979713c",
+        "practices": [],
+        "prerequisites": ["basics",
+          "bools",
+          "conditionals",
+          "lists",
+          "list-methods",
+          "loops",
+          "numbers",
+          "strings",
+          "string-methods"
+        ],
+        "difficulty": 4
+      },
       {
         "slug": "minesweeper",
         "name": "Minesweeper",