Update builder Go version

Updates the builder image, which updates:
- Go to 1.20.7 (from 1.20.5)
- FIPS Go 1.20.6 (from 1.20.5)

Changelog: changed

Author: Clemens Beck

.gitlab-ci.yml

@@ -42,7 +42,7 @@ variables:
   # To be used for images that exist only on dev.gitlab.org
   DEV_BUILDER_IMAGE_REGISTRY: 'dev.gitlab.org:5005/cookbooks/gitlab-omnibus-builder'
   PUBLIC_BUILDER_IMAGE_REGISTRY: "registry.gitlab.com/gitlab-org/gitlab-omnibus-builder"
-  BUILDER_IMAGE_REVISION: "4.20.0"
+  BUILDER_IMAGE_REVISION: "4.21.1"
   # The registry to pull the assets image from
   ASSET_REGISTRY: "${CI_REGISTRY}"
   ASSET_SYNC_EXISTING_REMOTE_FILES: "keep"

test-plans/upgrade-golang-testplan.md

@@ -3,8 +3,8 @@
 <!-- Copy and paste the following into your MR description. -->
 ## Test plan
 
-- [ ] QA tests passed for FIPS and non FIPS builds
-- [ ] Confirmed build was done with go 1.19 `strings /opt/gitlab/embedded/bin/gitaly  | grep 'go1\.' | tail -1`
+- [ ] QA tests passed for FIPS and non FIPS builds, including triggering the `build-package-on-all-os` job
+- [ ] Confirmed build was done with desired version of go `strings /opt/gitlab/embedded/bin/gitaly  | grep 'go1\.' | tail -1`
 - [ ] Confirmed Omnibus-built services that are owned by distribution are working
   - [ ] prometheus - (is scraping metrics)