Docs: add gif for vela def (#899)

Signed-off-by: Yin Da <yd219913@alibaba-inc.com>

docs/platform-engineers/cue/definition-edit.md

@@ -244,6 +244,10 @@ ComponentDefinition my-comp: My component.
 ComponentDefinition my-comp in namespace my-namespace deleted.
 ```
 
+A brief quick view for these commands are shown below.
+
+![def-demo](../../resources/veladef.gif)
+
 ## Next Step
 
 * Learn more about [defining customized component](../components/custom-component).

i18n/zh/docusaurus-plugin-content-docs/current/platform-engineers/cue/definition-edit.md

@@ -241,6 +241,10 @@ ComponentDefinition my-comp: My component.
 ComponentDefinition my-comp in namespace my-namespace deleted.
 ```
 
+下图简单展示了如何使用`vela def`命令来操作管理 Definition。
+
+![def-demo](../../resources/veladef.gif)
+
 ## 下一步
 
 * 了解如何使用 CUE [自定义组件](../components/custom-component)。

i18n/zh/docusaurus-plugin-content-docs/version-v1.5/platform-engineers/cue/definition-edit.md

@@ -241,6 +241,10 @@ ComponentDefinition my-comp: My component.
 ComponentDefinition my-comp in namespace my-namespace deleted.
 ```
 
+下图简单展示了如何使用`vela def`命令来操作管理 Definition。
+
+![def-demo](../../resources/veladef.gif)
+
 ## 下一步
 
 * 了解如何使用 CUE [自定义组件](../components/custom-component)。

versioned_docs/version-v1.5/platform-engineers/cue/definition-edit.md

@@ -244,6 +244,10 @@ ComponentDefinition my-comp: My component.
 ComponentDefinition my-comp in namespace my-namespace deleted.
 ```
 
+A brief quick view for these commands are shown below.
+
+![def-demo](../../resources/veladef.gif)
+
 ## Next Step
 
 * Learn more about [defining customized component](../components/custom-component).