Error when apiVersion is not set in a patch when creating cluster

[frezbo]

Bug Report

Gets an unable to decode keys error when a patch has apiVersion missing, or apiversion is mistyped

For example, this patch below triggers the error:

---
apiversion: v1alpha1
kind: ExtensionServicesConfig
config:
    - name: nut-client
      configFiles:
        - content: MONITOR ${upsmonHost} 1 remote pass foo
          mountPath: /usr/local/etc/nut/upsmon.conf

note that apiversion is misttyped

Description

A hacky patch is attached here, which doesn't seem to be correct

diff --git hack/release.toml hack/release.toml
index ef3b501e8..a7bd28339 100644
--- hack/release.toml
+++ hack/release.toml
@@ -6,7 +6,7 @@ github_repo = "siderolabs/talos"
 match_deps = "^github.com/((talos-systems|siderolabs)/[a-zA-Z0-9-]+)$"
 
 # previous release
-previous = "v1.6.3"
+previous = "v1.6.0"
 
 pre_release = true
 
diff --git pkg/machinery/config/configloader/internal/decoder/decoder.go pkg/machinery/config/configloader/internal/decoder/decoder.go
index 3e2a89e6c..70d67d206 100644
--- pkg/machinery/config/configloader/internal/decoder/decoder.go
+++ pkg/machinery/config/configloader/internal/decoder/decoder.go
@@ -16,12 +16,8 @@ import (
 	"github.com/siderolabs/talos/pkg/machinery/config/internal/registry"
 )
 
-var (
-	// ErrMissingKind indicates that the manifest is missing a kind.
-	ErrMissingKind = errors.New("missing kind")
-	// ErrMissingVersion indicates that the manifest is missing a version.
-	ErrMissingVersion = errors.New("missing apiVersion key")
-)
+// ErrMissingKind indicates that the manifest is missing a kind.
+var ErrMissingKind = errors.New("missing kind")
 
 const (
 	// ManifestAPIVersionKey is the string indicating a manifest's version.
@@ -128,8 +124,6 @@ func decode(manifest *yaml.Node) (target config.Document, err error) {
 	}
 
 	switch {
-	case version == "":
-		err = ErrMissingVersion
 	case version == "v1alpha1" && kind == "":
 		target, err = registry.New("v1alpha1", "")
 	case kind == "":
diff --git pkg/machinery/config/configpatcher/apply_test.go pkg/machinery/config/configpatcher/apply_test.go
index db8d578e1..2875970c3 100644
--- pkg/machinery/config/configpatcher/apply_test.go
+++ pkg/machinery/config/configpatcher/apply_test.go
@@ -98,13 +98,6 @@ func TestApplyMultiDocFail(t *testing.T) {
 	}
 }
 
-func TestValidateAPIVersion(t *testing.T) {
-	_, err := configpatcher.LoadPatches([]string{
-		"@testdata/multidoc/wrong-apiversion.yaml",
-	})
-	assert.EqualError(t, err, "missing apiVersion key")
-}
-
 func TestApplyMultiDoc(t *testing.T) {
 	patches, err := configpatcher.LoadPatches([]string{
 		"@testdata/multidoc/strategic1.yaml",
diff --git pkg/machinery/config/configpatcher/testdata/multidoc/wrong-apiversion.yaml pkg/machinery/config/configpatcher/testdata/multidoc/wrong-apiversion.yaml
deleted file mode 100644
index f7a8eefe1..000000000
--- pkg/machinery/config/configpatcher/testdata/multidoc/wrong-apiversion.yaml
+++ /dev/null
@@ -1,4 +0,0 @@
----
-apiversion: v1alpha1
-kind: SideroLinkConfig
-apiUrl: https://siderolink.api/join?jointoken=secret&user=alice