AWS – use session.NewSession instead of session.New to

`session.New` is deprecated and requires the `AWS_SDK_LOAD_CONFIG`
environment variable to be set in order to automatically call
`AssumeRoleWithWebIdentity` when `AWS_WEB_IDENTITY_TOKEN_FILE` is set
(which is not documented and most likely unintended).

cluster-autoscaler/cloudprovider/aws/aws_manager.go

@@ -146,9 +146,14 @@ func newAWSSDKProvider(cfg *provider_aws.CloudConfig) *awsSDKProvider {
 func getRegion(cfg ...*aws.Config) string {
 	region, present := os.LookupEnv("AWS_REGION")
 	if !present {
-		svc := ec2metadata.New(session.New(), cfg...)
-		if r, err := svc.Region(); err == nil {
-			region = r
+		sess, err := session.NewSession()
+		if err != nil {
+			klog.Errorf("Error getting AWS session while retrieving region: %v", err)
+		} else {
+			svc := ec2metadata.New(sess, cfg...)
+			if r, err := svc.Region(); err == nil {
+				region = r
+			}
 		}
 	}
 	return region
@@ -182,8 +187,11 @@ func createAWSManagerInternal(
 
 	if autoScalingService == nil || ec2Service == nil {
 		awsSdkProvider := newAWSSDKProvider(cfg)
-		sess := session.New(aws.NewConfig().WithRegion(getRegion()).
+		sess, err := session.NewSession(aws.NewConfig().WithRegion(getRegion()).
 			WithEndpointResolver(getResolver(awsSdkProvider.cfg)))
+		if err != nil {
+			return nil, err
+		}
 
 		if autoScalingService == nil {
 			autoScalingService = &autoScalingWrapper{autoscaling.New(sess), map[string]string{}}