build: Specify go 1.23.0 in go.mod (#7822)

We're using `.Keys()` a method of the maps package added in 1.23
(https://pkg.go.dev/maps@master#Keys) but our go.mod states 1.22.0. This
causes some in-IDE linting errors in VSCode.

Author: beautifulentropy

go.mod

@@ -1,6 +1,6 @@
 module github.com/letsencrypt/boulder
 
-go 1.22.0
+go 1.23.0
 
 require (
 	github.com/aws/aws-sdk-go-v2 v1.32.2