Fix Windows build issues relating to wpt test harness (#3429)

Author: npaun

src/workerd/api/tsconfig.json

@@ -15,5 +15,5 @@
     "allowJs": true
   },
   "include": ["**/*.ts"],
-  "exclude": []
+  "exclude": ["wpt/**"]
 }

src/workerd/api/wpt/tsconfig.json

@@ -26,6 +26,6 @@
       "wpt:*": ["../../../wpt/*"]
     }
   },
-  "include": ["**/*.ts"],
+  "include": ["**/*.ts", "../../../wpt/*.ts"],
   "exclude": []
 }