lib/plugins/aws/configCredentials/awsConfigCredentials.js/AwsConfigCredentials/getCredentials
class AwsConfigCredentials:  getCredentials() {
    // Get the credentials file lines
    const credentialsFileContent = this.serverless.utils.readFileSync(this.credentialsFilePath);
    return credentialsFileContent ? credentialsFileContent.split('\n') : [];
  }