Icu 6657 auth method model fragments refactor (#1507)

* refactor: 💡 Remove fragment usage for arrays in auth method
* chore: 🤖 Remove ember-data-model-fragments

✅ Closes: ICU-6657

addons/api/addon/transforms/account-claim-map-array.js

@@ -0,0 +1,16 @@
+import Transform from '@ember-data/serializer/transform';
+
+export default class AccountClaimMapArrayTransform extends Transform {
+  deserialize(serialized) {
+    const accountClaims = serialized || [];
+    return accountClaims.map((accountClaimString) => ({
+      from: accountClaimString.split('=')[0],
+      to: accountClaimString.split('=')[1],
+    }));
+  }
+
+  serialize(deserialized) {
+    const accountClaims = deserialized || [];
+    return accountClaims.map(({ from, to }) => `${from}=${to}`);
+  }
+}