fix govuln CI

[rach-id]

Currently, GoVulnCI is failing: https://github.com/celestiaorg/celestia-core/actions/runs/24179008927/job/70567025374?pr=2915

We should fix it.

Acceptance criteria:

• CI no failing anymore

[SillyZir]

Likely a newly published vulnerability in a transitive dependency — since the Makefile runs govulncheck@latest, the fix is either upgrading the flagged dep in go.mod or pinning govulncheck to a known-passing version.