fix: Wrap an entrypoint by async to handle exceptions correctly

src/index.ts

@@ -1,8 +1,10 @@
 import * as core from '@actions/core';
 import * as main from './main';
 
+(async () => {
   try {
-  main.run();
+    await main.run();
   } catch (e) {
     core.setFailed(`Action failed with error ${e}`);
   }
+})();