Support for disabling legacy IMDS endpoints in the OCI builder

[yugalarora]

Description

I've added support for disabling legacy IMDS endpoints in the OCI builder.

This introduces a new boolean option, instance_options_are_legacy_imds_endpoints_disabled, to the OCI builder configuration.

When you set this to true, the launched OCI instance will be configured to disable the legacy IMDSv1 endpoints. This enhances security by enforcing the use of IMDSv2.

Resolved Issues

If your PR resolves any open issue(s), please indicate them like this so they will be closed when your PR is merged:

Closes [#69 ]

Rollback Plan

If a change needs to be reverted, we will roll out an update to the code within 7 days.

Changes to Security Controls

N/A

[shivanshsinghraghuvanshi]

Can we please get it reviewed

[anshulsharma-hashicorp]

Can we please get it reviewed

Could you please add unit test cases for this change also generate check is breaking. please run make generate command and add the generated code as well in the same PR.

[anshulsharma-hashicorp]

Can we please get it reviewed

Could you please add unit test cases for this change also generate check is breaking. please run make generate command and add the generated code as well in the same PR.

Also please check this PR https://github.com/hashicorp/packer-plugin-oracle/pull/134/files for ref, if this looks okay we can go ahead with this, just let me know.

[hashicorp-cla-app]

All committers have signed the CLA.

[yugalarora]

@anshulsharma-hashicorp Done, please check now.

[anshulsharma-hashicorp]

@anshulsharma-hashicorp Done, please check now.

Hey please sign the CLA

[anshulsharma-hashicorp]

Also please check the formatting of the file in your mock file, please check the imports as lint check is breaking.

[anshulsharma-hashicorp]

LGTM