User Name not in credentials CSV file by default

### Describe the feature

When downloading CLI credentials from the IAM console, User Name is not an included header. However, User Name is expected when running `aws configure import –csv file://credentials.csv` as it is used for the profile name.

### Use Case

It is a frustrating manual step to have to open the file and add a User Name.

### Proposed Solution

Possible solution is to prompt the user if "User Name" is not found in CSV file to specify what they want their profile to be called.

### Other Information

_No response_

### Acknowledgements

- [ ] I may be able to implement this feature request
- [ ] This feature might incur a breaking change

### CLI version used

latest

### Environment details (OS name and version, etc.)

macOS Ventura