Add OIDC for using remote GCP servers in the benchmark submodule

What does this MR do?

OIDC allows managing/accessing GCP resources without setting up GCP credentials in variables, thus avoiding the risks of leaking secrets.

OIDC has to be configured on a project basis. This means that, Add OIDC for GCP authentication (sast-ide-benchmark!10 - merged) • Hua Yan • 17.4 cannot be reused in sast-ide-integration.

This MR sets up OIDC for sast-ide-integration.

What are the relevant issue numbers?

SAST IDE benchmark: use OIDC for GCP authentica... (gitlab-org/gitlab#473433 - closed) • Hua Yan • 17.3

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated for GitLab EE, if necessary
• Documentation created/updated for this project, if necessary
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Job definition updated, if necessary
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• Ensure the report version matches the equivalent schema version
• Conforms to the code review guidelines
• Conforms to the Go guidelines
• Security reports checked/validated by reviewer