Shogo Nakano

## Description - There is a comment by @bcoe that says TODO [here](https://github.com/googleapis/google-auth-library-nodejs/blob/main/src/auth/googleauth.ts#L206-L232). So I deleted Promises and changed to use async/await only. ## Check list - [x] Make sure...

Refactoring: Quit mixing Promises and async/await

2

### Problem - There is a comment by @bcoe that says `TODO`. This comment has been here for two years. - https://github.com/googleapis/google-auth-library-nodejs/blob/main/src/auth/googleauth.ts#L206-L232 ### Suggestion - It would be better to...