Update package.json for Mastra integration (#225)

Author: NathanTarbert

typescript-sdk/integrations/mastra/package.json

@@ -1,7 +1,7 @@
 {
   "name": "@ag-ui/mastra",
   "version": "0.0.5",
-  "license": "Elastic-2.0",
+  "license": "Apache-2.0",
   "main": "./dist/index.js",
   "module": "./dist/index.mjs",
   "types": "./dist/index.d.ts",