enable IMDSv2 for linuxkit

[kalyanim7]

Description

Recently , AWS enabled IMDSv2 authentication as mandatory and the existing instances which are using IMDS are highly vulnerable.

Steps to reproduce the issue:

Describe the results you received:

Ensure Instances are configured with IMDSv2

Describe the results you expected:
Code needs to be updated to enable IMDSv2 for this function,
https://github.com/linuxkit/linuxkit/blob/master/pkg/metadata/provider_aws.go#L79

TOKEN=curl -X PUT "http://169.254.169.254/latest/api/token" -H "X-aws-ec2-metadata-token-ttl-seconds: 21600"
&& curl -H "X-aws-ec2-metadata-token: $TOKEN" -v http://169.254.169.254/latest/meta-data/

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instancedata-data-retrieval.html

Additional information you deem important (e.g. issue happens only occasionally):