Add log level check to gate IMDSv1 fallback warning

[RanVaknin]

Description
Addresses #5116
This PR updates the logging behavior in the EC2Metadata token provider (token_provider.go). It modifies the conditions under which the warning message about falling back to IMDSv1 is logged.

Changes
The warning "WARN: failed to get session token, falling back to IMDSv1" in the fetchTokenHandler method is now conditioned on the LogLevel being set to LogDebugWithDeprecated.
This update prevents the warning from being logged when the LogLevel is configured to suppress such messages.

Testing
This testing setup demonstrates the modified behavior of the EC2Metadata token provider, using a custom HTTP transport to simulate conditions that trigger a fallback to IMDSv1. The test verifies that the warning message is conditionally logged based on the LogLevel setting, ensuring it aligns with the configured log suppression.

package main

import (
	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/credentials"
	"github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds"
	"github.com/aws/aws-sdk-go/aws/ec2metadata"
	"github.com/aws/aws-sdk-go/aws/session"
	"net/http"
)

// mock a response that would trigger IMDSv1 fallback
type CustomTransport struct {
	Transport http.RoundTripper
}

func (t *CustomTransport) RoundTrip(req *http.Request) (*http.Response, error) {
	return &http.Response{
		StatusCode: http.StatusForbidden,
		Body:       http.NoBody,
		Header:     make(http.Header),
	}, nil
}

func main() {
	sess, _ := session.NewSession(&aws.Config{
		Region:   aws.String("us-east-1"),
		//LogLevel: aws.LogLevel(aws.LogDebugWithDeprecated), // would raise the warning
		LogLevel: aws.LogLevel(aws.LogOff), // would not raise this warning
		HTTPClient: &http.Client{
			Transport: &CustomTransport{Transport: http.DefaultTransport},
		},
	})
	ec2MetaClient := ec2metadata.New(sess, &aws.Config{})

	creds := credentials.NewCredentials(&ec2rolecreds.EC2RoleProvider{
		Client: ec2MetaClient,
	})

	_, _ = creds.Get()
}