Package: Validate challenges on test (#17216)

This PR allows us to validate the schema during test.

It also removes some cruft from the seed files and ensures only the required data is packaged and consumable, reducing the package weight somewhat.

Author: Bouncey

challenges/01-responsive-web-design/applied-accessibility.json

@@ -23,7 +23,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -65,7 +64,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -120,7 +118,6 @@
       "hints": [
         "All the h5 tags are siblings, and should be changed to the same new heading level."
       ],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -173,7 +170,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -220,7 +216,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -287,7 +282,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -357,7 +351,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -432,7 +425,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -527,7 +519,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -593,7 +584,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -674,7 +664,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -758,7 +747,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -849,7 +837,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -918,7 +905,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -1001,7 +987,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -1122,7 +1107,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -1179,7 +1163,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -1231,7 +1214,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -1284,7 +1266,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -1340,7 +1321,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -1401,7 +1381,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},
@@ -1497,7 +1476,6 @@
       ],
       "solutions": [],
       "hints": [],
-      "type": "waypoint",
       "releasedOn": "Feb 17, 2017",
       "challengeType": 0,
       "translations": {},