Environment variable support for SSO

### Describe the feature

A lot of CLI configuration can be controlled via environment variables, but the SSO parameters are not available. Reference: https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-envvars.html

### Use Case

If I can pass in configuration via env vars it makes it easier to automate writing out the credentials file. Expanded:

1. write a config
2. get credentials
3. write a config again

If I can set sso params as env vars, I can reduce it down to:

1. get credentials
2. write a config

Additionally this is useful in scenarios like:

- Read only file system
- ci/cd where you don't want to risk inclusion

### Proposed Solution

_No response_

### Other Information

_No response_

### Acknowledgements

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

### CLI version used

2

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

linux