Remove default export

We don't use default exports in our libraries. This commit changes
`SmartTransactionsController` from a default export to a named export.

Author: mcmire

CHANGELOG.md

@@ -19,6 +19,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Upgrade `@metamask/base-controller` from `^7.0.1` to `^8.3.0` ([#529](https://github.com/MetaMask/smart-transactions-controller/pull/529))
 - Upgrade `@metamask/polling-controller` from `^12.0.0` to `^14.0.0` ([#529](https://github.com/MetaMask/smart-transactions-controller/pull/529))
 
+### Removed
+
+- **BREAKING:** Remove default export
+  - Use `import { SmartTransactionsController } from '@metamask/smart-transactions-controller'` instead.
+
 ## [18.1.0]
 
 ### Added

src/SmartTransactionsController.ts

@@ -220,7 +220,7 @@ export type SmartTransactionsControllerPollingInput = {
   chainIds: Hex[];
 };
 
-export default class SmartTransactionsController extends StaticIntervalPollingController<SmartTransactionsControllerPollingInput>()<
+export class SmartTransactionsController extends StaticIntervalPollingController<SmartTransactionsControllerPollingInput>()<
   typeof controllerName,
   SmartTransactionsControllerState,
   SmartTransactionsControllerMessenger

src/index.test.ts

@@ -1,4 +1,4 @@
-export { default } from './SmartTransactionsController';
+export { SmartTransactionsController } from './SmartTransactionsController';
 export type {
   SmartTransactionsControllerMessenger,
   SmartTransactionsControllerState,