chore: update Go version to 1.25.3

Update minimum Go version from 1.23.0 to 1.25.3 to address
standard library security vulnerabilities including:
- GO-2025-4007: Quadratic complexity in crypto/x509 name constraints

This ensures the codebase uses the latest stable Go version with
all security fixes.

Author: vnykmshr

go.mod

@@ -1,6 +1,6 @@
 module github.com/vnykmshr/obcache-go
 
-go 1.23.0
+go 1.25.3
 
 require (
 	github.com/hashicorp/golang-lru/v2 v2.0.7