upgrade metadata call to use IMDSv2, only supported version soon (#180)

Summary:
Soon we will only support metadata fetching for EC2 instances via IMDSv2 - this upgrades the existing v1 call to a v2 call - no functional changes

Pull Request resolved: #180

Test Plan: testing if the run_tests.yaml correctly fetches the instance metadata

Reviewed By: yifuwang

Differential Revision: D65450634

Pulled By: wdvr

fbshipit-source-id: 08cc0b6e7ff7f8fec2986c77bfd83c84fea53b92

.github/workflows/run_tests.yaml

@@ -63,7 +63,7 @@ jobs:
             # Pulled from instance metadata endpoint for EC2
             # see https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instancedata-data-retrieval.html
             category=$1
-            curl -fsSL "http://169.254.169.254/latest/meta-data/${category}"
+            curl -H "X-aws-ec2-metadata-token: $(curl -s -X PUT "http://169.254.169.254/latest/api/token" -H "X-aws-ec2-metadata-token-ttl-seconds: 30")" -fsSL "http://169.254.169.254/latest/meta-data/${category}"
           }
           echo "ami-id: $(get_ec2_metadata ami-id)"
           echo "instance-id: $(get_ec2_metadata instance-id)"