Prevent Unnecessary Version Bumps in go.mod During Go Version Updates (#20781)

* Prevent Unnecessary Version Bumps in `go.mod` During Go Version Updates

This PR addresses issue #20770, where the minikube automation (triggered by make `update-golang-version`) unnecessarily bumped minor or patch versions in `go.mod` when updating the Go version. Following Kubernetes' practice, which avoids such bumps in `go.mod`, this change ensures only the go directive is updated to the stable Go version.

**Changes:**
- Added `go.mod` to the schema map in `hack/update/golang_version/update_golang_version.go` with a regex (go 1\.\d+\.\d+) to update the go directive to {{.StableVersion}} (e.g., go 1.24.2).
- This ensures the automation updates only the go directive without modifying module dependencies, aligning with Kubernetes' `go.mod` behavior.

**Impact:**
- Running make `update-golang-version` now updates the go directive (e.g., from go 1.22.3 to go 1.24.2) without unintended dependency version bumps.
- Tested by setting go 1.22.3 in go.mod, running go mod tidy and make update-golang-version, and verifying only the go directive and toolchain changed.

fixes: #20773

* Pin `go.mod` to Major.Minor Go Version (e.g., `1.24.0`)

**Description**:
Fixes #20773 by updating the automation to pin the `go` directive in `go.mod` to the major.minor Go version (e.g., `1.24.0`) instead of the full version (e.g., `1.24.2`), aligning with Kubernetes’ `go.mod`. This prevents breaking users relying on minikube packages.

**Changes**:
- Modified `hack/update/golang_version/update_golang_version.go` to compute `MajorMinor` version (e.g., `1.24.0`) from `StableVersion`.
- Updated `schema` to set `go.mod`’s `go` directive to `{{.MajorMinor}}`.
- Tested by setting `go 1.23.4`, running `make update-golang-version`, and verifying `go 1.24.0` with no dependency bumps.

**Closes**: #20773

* Reverted all 66 files to upstream master except update_golang_version.go

Author: Victorthedev

hack/update/golang_version/update_golang_version.go

@@ -36,6 +36,11 @@ var (
 	}
 
 	schema = map[string]update.Item{
+		"go.mod": {
+			Replace: map[string]string{
+				`go 1\.\d+\.\d+`: `go {{.MajorMinor}}`, // Match and replace only the major.minor Go version
+			},
+		},
 		"Makefile": {
 			Replace: map[string]string{
 				// searching for 1.* so it does NOT match "KVM_GO_VERSION ?= $(GO_VERSION:.0=)" in the Makefile
@@ -74,8 +79,8 @@ var (
 // Data holds stable Golang version - in full and in <major>.<minor> format
 type Data struct {
 	StableVersion string
+	MajorMinor    string // Major.minor version (e.g., 1.24.0)
 	K8SVersion    string // as of v1.23.0 Kubernetes uses k8s version in golang image name because: https://github.com/kubernetes/kubernetes/pull/103692#issuecomment-908659826
-
 }
 
 func main() {
@@ -91,8 +96,13 @@ func main() {
 		klog.Warningf("Golang stable version is a release candidate, skipping: %s", stable)
 		return
 	}
-	data := Data{StableVersion: stable, K8SVersion: k8sVersion}
-	klog.Infof("Golang stable version: %s", data.StableVersion)
+	// Derive major.minor version (e.g., 1.24.0 from 1.24.2)
+	majorMinor := stable
+	if parts := strings.Split(stable, "."); len(parts) >= 3 {
+		majorMinor = fmt.Sprintf("%s.%s.0", parts[0], parts[1])
+	}
+	data := Data{StableVersion: stable, MajorMinor: majorMinor, K8SVersion: k8sVersion}
+	klog.Infof("Golang stable version: %s, MajorMinor: %s", data.StableVersion, data.MajorMinor)
 
 	update.Apply(schema, data)