all: with 1.23 out, update Go directive to Go 1.22

Now that 1.23 is out, and 1.19 and 1.20 trybots have been updated to be
optional in CL 610395, we can update the go.mod files to use Go 1.22.6.
This will unblock tagging x-repos, since there won't be conflicts with
x/mod.

A subsequent CL will update the gopls go.mod file to 1.23.1, once that
minor version is released (shortly).

For golang/go#65917

Change-Id: I663918f7be5a3e340703ae82e13b93e9e0f2877d
Reviewed-on: https://go-review.googlesource.com/c/tools/+/610435
LUCI-TryBot-Result: Go LUCI <[email protected]>
Auto-Submit: Robert Findley <[email protected]>
Reviewed-by: Alan Donovan <[email protected]>

Author: findleyr

go.mod

@@ -1,6 +1,6 @@
 module github.com/apstndb/gotoolsdiff
 
-go 1.19 // => default GODEBUG has gotypesalias=0
+go 1.22.6 // => default GODEBUG has gotypesalias=0
 
 require (
 	github.com/google/go-cmp v0.6.0