build: set min build version to Go 1.22.6

Go 1.23 was released this week, so with this PR we update the build
system to officially support the last two releases.

make/builder.Dockerfile

@@ -3,7 +3,7 @@
 # /dev.Dockerfile
 # /.github/workflows/main.yml
 # /.github/workflows/release.yml
-FROM golang:1.22.5-bookworm
+FROM golang:1.22.6-bookworm
 
 MAINTAINER Olaoluwa Osuntokun <laolu@lightning.engineering>