message: remove references to non-existent snippets.
diff: @@ -183,14 +183,6 @@ This attribute controls whether the property field is read-only. If the attribut
  | **Is Required** | No |
  | **Default Value** | No override |
  -```ts
  -[[include:Presentation.Content.Customization.PropertySpecification.IsReadOnly.Ruleset]]
  -```
  -
  -```ts
  -[[include:Presentation.Content.Customization.PropertySpecification.IsReadOnly.Result]]
  -```
  -
  ### Attribute `priority`
  This attribute controls the order in which property fields should be displayed. Property fields with higher priority
  @@ -203,10 +195,6 @@ will be the maximum priority of its properties.
  | **Is Required** | No |
  | **Default Value** | No override |
  -```ts
  -[[include:Presentation.Content.Customization.PropertySpecification.Priority.Ruleset]]
  -```
  -
  | `priority: 0` | `priority: 9999` |
  | ------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------- |
  | ![Example when "priority" attribute value is set to 0](./media/propertyspecification-with-priority-attribute-0.png) | ![Example when "priority" attribute value is set to 9999](./media/propertyspecification-with-priority-attribute-9999.png) |
  