Update test examples.json aws config to refer renamed mbed-os-example-for-aws repo

Author: rajkan01

tools/test/examples/examples.json

@@ -468,8 +468,8 @@
         "auto-update" : true
     },
     {
-      "name": "mbed-os-example-aws",
-      "github": "https://github.com/ARMmbed/mbed-os-example-aws",
+      "name": "mbed-os-example-for-aws",
+      "github": "https://github.com/ARMmbed/mbed-os-example-for-aws",
       "sub-repo-example": false,
       "subs": [],
       "features" : [],