fix(cve): CVE-2026-42505 - update Go stdlib to 1.25.12

- Update go directive from 1.25.11 to 1.25.12
- Fixes Encrypted Client Hello (ECH) privacy leak in crypto/tls
- crypto/tls in Go 1.25.11 exposes cleartext SNI when invoking ECH

Fixes: CVE-2026-42505 (GO-2026-5856)

Co-Assisted-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: divyansh42

go.mod

@@ -1,6 +1,6 @@
 module github.com/tektoncd/cli
 
-go 1.25.11
+go 1.25.12
 
 require (
 	github.com/AlecAivazis/survey/v2 v2.3.7