fix(wasm-sdk): add maxLength to indexed rarity field in test fixture

The validation feature added to rs-sdk's dpp dependency now enforces
that indexed string properties must have maxLength <= 63. The rarity
field in the crypto card game test fixture was missing this constraint,
causing all DataContract tests to fail.

Author: thepastaclaw

packages/wasm-sdk/tests/unit/fixtures/data-contract-v0-crypto-card-game.ts

@@ -52,6 +52,7 @@ const contract = {
         rarity: {
           type: 'string',
           description: 'Rarity level of the card',
+          maxLength: 9,
           enum: [
             'common',
             'uncommon',