bug(PopConfirmButtom): throw exception cause dispose (#4225)

* fix: 更新脚本防止报错

* chore: bump version 8.9.1

Author: ArgoZhang

src/BootstrapBlazor/BootstrapBlazor.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Razor">
 
   <PropertyGroup>
-    <Version>8.9.1-beta05</Version>
+    <Version>8.9.1</Version>
   </PropertyGroup>
 
   <ItemGroup Condition="'$(TargetFramework)' == 'net5.0'">

src/BootstrapBlazor/Components/Button/PopConfirmButton.razor.js

@@ -49,7 +49,9 @@ export function init(id) {
             clearTimeout(handler);
             const hasConfirm = el.hasAttribute('data-bb-confirm');
             if (hasConfirm) {
-                confirm.popover.dispose();
+                if (confirm.popover.tip) {
+                    confirm.popover.dispose();
+                }
                 delete confirm.popover;
             }
         }, 50);