remove wildcard exports

This causes the following call, made by the Codegen infrastructure during React Native autolinking (specifically `node_modules/react-native-macos/scripts/codegen/generate-artifacts-executor/utils.js`):

```js
require.resolve(
  "@nativescript/macos-node-api/package.json",
  { paths: [projectRoot]}
)
```

... to fail. It unexpectedly resolves our index.js file rather than the package.json, and then proceeds to JSON.parse() our index.js file.

Author: shirakaba

packages/macos/package.json

@@ -54,10 +54,6 @@
     ".": {
       "types": "./index.d.ts",
       "default": "./index.js"
-    },
-    "./*": {
-      "types": "./*.d.ts",
-      "default": "./index.js"
     }
   }
 }