fix: Modify settings panel icons (opentiny#1612)

Author: xuanlid

packages/design-core/assets/event.svg

@@ -3,5 +3,5 @@ export default {
   title: '高级',
   type: 'plugins',
   name: 'event',
-  icon: 'target'
+  icon: 'event'
 }

packages/design-core/assets/property.svg

@@ -3,5 +3,5 @@ export default {
   title: '属性',
   type: 'plugins',
   name: 'props',
-  icon: 'form'
+  icon: 'property'
 }

packages/design-core/assets/style.svg

@@ -3,5 +3,5 @@ export default {
   title: '样式',
   name: 'style',
   type: 'plugins',
-  icon: 'display-inline'
+  icon: 'style'
 }