update to go1.20.9, test go1.21.2

go1.20.9 (released 2023-10-05) includes one security fixes to the cmd/go package,
as well as bug fixes to the go command and the linker. See the Go 1.20.9
milestone on our issue tracker for details:

https://github.com/golang/go/issues?q=milestone%3AGo1.20.9+label%3ACherryPickApproved

full diff: https://github.com/golang/go/compare/go1.20.8...go1.20.9

From the security mailing:

[security] Go 1.21.2 and Go 1.20.9 are released

Hello gophers,

We have just released Go versions 1.21.2 and 1.20.9, minor point releases.

These minor releases include 1 security fixes following the security policy:

- cmd/go: line directives allows arbitrary execution during build

  "//line" directives can be used to bypass the restrictions on "//go:cgo_"
  directives, allowing blocked linker and compiler flags to be passed during
  compliation. This can result in unexpected execution of arbitrary code when
  running "go build". The line directive requires the absolute path of the file in
  which the directive lives, which makes exploting this issue significantly more
  complex.

  This is CVE-2023-39323 and Go issue https://go.dev/issue/63211.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit 9cc6e5b27f)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

.github/workflows/ci.yml

@@ -25,7 +25,7 @@ jobs:
     - name: Set up Go
       uses: actions/setup-go@v2
       with:
-        go-version: 1.20.8
+        go-version: 1.20.9
 
     - name: Dependencies
       run: |

Dockerfile

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1
 
-ARG GO_VERSION=1.20.8
+ARG GO_VERSION=1.20.9
 ARG ALPINE_VERSION=3.18
 ARG XX_VERSION=1.2.1