ASP-1893: Bump Go to 1.26.2 for kafka-topic-creator image

Fixes Go stdlib CVEs (CVE-2025-68121, CVE-2025-61726, CVE-2026-25679,
CVE-2026-32280, etc.) flagged by Trivy scan in CI.

- Dockerfile: golang 1.22.7 → 1.26.2
- go.mod: go 1.22.7 → 1.26.2

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: suresh-prakash

kafka-topic-creator/Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.22.7 AS builder
+FROM golang:1.26.2 AS builder
 COPY src/main/go /opt
 WORKDIR /opt
 

kafka-topic-creator/src/main/go/go.mod

@@ -1,6 +1,6 @@
 module hypertrace.org/kafka-topic-creator
 
-go 1.22.7
+go 1.26.2
 
 require (
 	github.com/confluentinc/confluent-kafka-go/v2 v2.5.3