Rebuild with latest stable go (1.23.8) with security fixes and other dependencies update

What's Changed

• Build image with go 1.23.8 by @ldemailly in #1026
• Bump golang.org/x/net from 0.37.0 to 0.38.0 by @dependabot in #1023
• Logo w fortio text included by @ldemailly in #1024
• Bump google.golang.org/grpc from 1.71.0 to 1.71.1 by @dependabot in #1025

Full Changelog: v1.68.1...v1.68.2