Refactor wwctl <node|profile> edit and fix bugs

`wwctl node edit` appears to not be working properly since MergeNode. This
refactor, partly towards #918, resolves the issues with `node edit` and updates
`profile edit` to match.

Signed-off-by: Jonathon Anderson <janderson@ciq.com>

internal/pkg/node/modifiers.go

@@ -6,9 +6,9 @@ import (
 	"os"
 
 	"github.com/pkg/errors"
-	"gopkg.in/yaml.v3"
 
 	warewulfconf "github.com/warewulf/warewulf/internal/pkg/config"
+	"github.com/warewulf/warewulf/internal/pkg/util"
 	"github.com/warewulf/warewulf/internal/pkg/wwlog"
 )
 
@@ -136,10 +136,8 @@ func (config *NodesYaml) PersistToFile(configFile string) error {
 	return nil
 }
 
-/*
-Dump returns a YAML document representing the nodeDb
-instance. Passes through any errors generated by yaml.Marshal.
-*/
+// Dump returns a YAML document representing the nodeDb instance. Passes through any errors
+// generated by yaml encoding.
 func (config *NodesYaml) Dump() ([]byte, error) {
 	// flatten out profiles and nodes
 	for _, val := range config.NodeProfiles {
@@ -148,10 +146,5 @@ func (config *NodesYaml) Dump() ([]byte, error) {
 	for _, val := range config.Nodes {
 		val.Flatten()
 	}
-	var buf bytes.Buffer
-	// Run through encoder
-	yamlEncoder := yaml.NewEncoder(&buf)
-	yamlEncoder.SetIndent(2)
-	err := yamlEncoder.Encode(config)
-	return buf.Bytes(), err //yaml.Marshal(config)
+	return util.EncodeYaml(config)
 }