fix: get rid of side effect

Author: hunterliu1003

packages/vue-final-modal/src/components/CoreModal/useTransition.ts

@@ -1,5 +1,5 @@
 import type { BaseTransitionProps, ComputedRef, Ref, TransitionProps } from 'vue'
-import { computed, nextTick, onMounted, ref, watch } from 'vue'
+import { computed, nextTick, ref, watch } from 'vue'
 import type CoreModal from './CoreModal.vue'
 
 export enum TransitionState {
@@ -95,13 +95,6 @@ export function useTransition(
     }
   })
 
-  onMounted(() => {
-    if (visible.value) {
-      onEntering()
-      onEnter()
-    }
-  })
-
   async function enterTransition() {
     visible.value = true
     await nextTick()