chore(label): new label "values-from"

This labels allow to use some environment variables from another service
and use the configMap / secret instead of the original value. This is
useful to avoid duplication of values for several variables.

generator/labels/labelStructs/valueFrom.go

@@ -0,0 +1,13 @@
+package labelStructs
+
+import "gopkg.in/yaml.v3"
+
+type ValueFrom map[string]string
+
+func GetValueFrom(data string) (*ValueFrom, error) {
+	vf := ValueFrom{}
+	if err := yaml.Unmarshal([]byte(data), &vf); err != nil {
+		return nil, err
+	}
+	return &vf, nil
+}