[IND-4227][COMPLIANCE] chore: Fix lint issues-build tags

[ssagarverma]

This change is required to fix lint issues that appeared during CI checks in #566.

Replaced all deprecated // +build directives with the modern //go:build form
introduced in Go 1.17. This modernizes build constraints to align with the Go 1.24
toolchain and removes obsolete syntax flagged by go vet linter.

No runtime or functional behavior changes.

⚠️ Note: This change drops compatibility with Go versions earlier than 1.17,
as they do not support the //go:build syntax.

PCI review checklist

• I have documented a clear reason for, and description of, the change I am making.

• If applicable, I've documented a plan to revert these changes if they require more than reverting the pull request.

• If applicable, I've documented the impact of any changes to security controls.

  Examples of changes to security controls include using new access control methods, adding or removing logging pipelines, etc.

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