update to go1.22.6

- https://github.com/golang/go/issues?q=milestone%3AGo1.22.6+label%3ACherryPickApproved
- full diff: https://github.com/golang/go/compare/go1.22.5...go1.22.6

go1.22.6 (released 2024-08-06) includes fixes to the go command, the compiler,
the linker, the trace command, the covdata command, and the bytes, go/types,
and os/exec packages. See the Go 1.22.6 milestone on our issue tracker for
details.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Vagrantfile

@@ -104,7 +104,7 @@ EOF
   config.vm.provision "install-golang", type: "shell", run: "once" do |sh|
     sh.upload_path = "/tmp/vagrant-install-golang"
     sh.env = {
-        'GO_VERSION': ENV['GO_VERSION'] || "1.22.5",
+        'GO_VERSION': ENV['GO_VERSION'] || "1.22.6",
     }
     sh.inline = <<~SHELL
         #!/usr/bin/env bash