Update Go toolchain version in go.mod to address security vulnerabilities

[iAlan02]

Summary

The current go.mod for Conftest v0.69.0 specifies an outdated Go toolchain version.

Updating the minimum Go version to the latest supported patch release would ensure the project is built with a toolchain that includes the latest security fixes.

Reference:

• https://github.com/open-policy-agent/conftest/blob/v0.69.0/go.mod

Motivation

Recent Go security releases have fixed several vulnerabilities in both the Go standard library and the Go toolchain. Projects built with older Go versions may continue to be flagged by vulnerability scanners even when the application code itself is not directly affected.

Some of the addressed vulnerabilities include:

• CVE-2025-61726 – Go standard library vulnerability.
• CVE-2025-61728 – Go standard library vulnerability.
• CVE-2025-68119 – Go toolchain execution vulnerability.

Updating the Go toolchain would help ensure that Conftest is built and released using a version that incorporates these fixes.

Proposed change

• Update the Go version declared in go.mod to the latest supported patch release.
• Update the CI/build environment to use the same Go version.

Benefits

• Includes the latest Go security fixes.
• Reduces vulnerability findings reported by SCA/security scanners.
• Keeps the project aligned with Go's supported release policy.
• Improves long-term maintainability and security posture.

Additional context

Go security releases regularly include fixes for vulnerabilities in both the standard library and the compiler/toolchain. Using a fully patched Go release is recommended for actively maintained projects, even when no application code changes are required.