Disable metadata for AWS cli v2 in container entrypoint

The v2 AWS cli throws an exception if run on Azure, e.g.
via Github Actions due to presumeabley due to the metadata
service using the same IP address.

Apparently handling exceptions is too difficult for AWS.

aws/aws-cli#5262
aws/aws-cli#5623

oci/entrypoint_user

@@ -12,7 +12,7 @@ if [ -x "$(command -v aws)" ]; then
   # handle base64 encoded AWS crendentials
   if [ ! -z "$KBST_AUTH_AWS" ]; then
     echo "$KBST_AUTH_AWS" | base64 --decode > $AWS_CONFIG_PATH/credentials
-    aws sts get-caller-identity
+    AWS_EC2_METADATA_DISABLED=true aws sts get-caller-identity
   fi
 fi