Add doc comments for two methods

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

internal/pkg/node/modifiers.go

@@ -135,6 +135,8 @@ func (config *NodeYaml) Persist() error {
 }
 
 
+// Dump returns a YAML document representing the nodeDb
+// instance. Passes through any errors generated by yaml.Marshal.
 func (config *NodeYaml) Dump() ([]byte, error) {
 	// flatten out profiles and nodes
 	for _, val := range config.NodeProfiles {