Enable different output "format" for earthaccess.get_s3_credentials

[jbusecke]

I am finding myself having to 'translate' the credentials dict returned from earthaccess.get_s3_credentials quite frequently, e.g. for

• fsspec: {'key': creds['accessKeyId'], 'secret':creds['secretAccessKey'], 'token':creds['sessionToken']}
• obstore: { "access_key_id": creds['accessKeyId'], "secret_access_key": creds['secretAccessKey'], "token": creds['sessionToken'], "expires_at": dt.datetime.fromisoformat(creds['expiration']), }
• icechunk: icechunk.s3_static_credentials( access_key_id=creds['accessKeyId'], secret_access_key=creds['secretAccessKey'], expires_after=dt.datetime.fromisoformat(creds['expiration']), session_token=creds['sessionToken'] )

As a convenience solution I wonder if we could implement an option like this:

earthaccess.get_s3_credentials(format='fsspec') -> Dict
earthaccess.get_s3_credentials(format='obstore') -> Dict
earthaccess.get_s3_credentials(format='icechunk') -> icechunk.S3StaticCredentials