go.mod: bump to Go 1.22

The newer version is required when checking packages which need Go 1.22.
From a csi-lib-utils CI run with Go 1.22.2 in the PATH and Kubernetes 1.30
in vendor:

   /home/prow/go/src/github.com/kubernetes-csi/csi-lib-utils/vendor/k8s.io/apimachinery/pkg/api/resource/amount.go:17:1: package requires newer Go version go1.22

This feels like a workaround and raises the question whether this has to be
done for each new Go release. Discussed in
golang/go#67282.

go.mod

@@ -1,6 +1,6 @@
 module sigs.k8s.io/logtools
 
-go 1.20
+go 1.22
 
 require (
 	golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842