ci: ovn-kubernetes: Move our CI jobs to OVN-K release-1.2 branch.

This is the latest stable release branch ovn-kubernetes supports since
the v1.2.0 release:

https://github.com/ovn-kubernetes/ovn-kubernetes/releases/tag/v1.2.0

This release is the first ovnk release that uses OVN's transit routers
so it's interesting for us to use its tests.

Unfortunately we also had to do a minor change in the helper that
detects with golang version needs to be installed.  We used to use what
is stored in ovnk's go.mod file but on branch release-1.2 that points to
1.24.0.

If we use the value as is eventually the job will try to pull the
quay.io/projectquay/golang:1.24.0 image.  That doesn't exist.  It turns
out a better way to detect the golang version is to look at
dist/images/Makefile.  It's still not bullet proof and it might change
in the future but likely not on ovnk's stable release branch.
It seems to work for now.

Signed-off-by: Dumitru Ceara <dceara@redhat.com>
Signed-off-by: Ales Musil <amusil@redhat.com>
(cherry picked from commit 6ff153d)

Author: dceara

.ci/ovn-kubernetes/prepare.sh

@@ -7,7 +7,8 @@ env_path=$2
 topdir=$PWD
 
 function extract_go_version() {
-    go mod edit -json go-controller/go.mod | jq -r .Go
+    grep -E 'GO_VERSION \?= [0-9]\.[0-9\.]*$' dist/images/Makefile \
+        | awk '{print $3}' | tr -d '"'
 }
 
 function extract_k8s_version() {

.github/workflows/ovn-kubernetes.yml

@@ -13,7 +13,7 @@ concurrency:
   cancel-in-progress: true
 
 env:
-  OVNKUBE_COMMIT: "release-1.1"
+  OVNKUBE_COMMIT: "release-1.2"
   KIND_CLUSTER_NAME: ovn
   KIND_INSTALL_INGRESS: true
   KIND_ALLOW_SYSTEM_WRITES: true