refactor: 调整基金会图片样式

Author: ArgoZhang

src/BootstrapBlazor.Server/Components/Pages/Index.razor

@@ -37,8 +37,8 @@
         <img alt="barcode" class="barcode" src="./images/[email protected]" />
     </div>
     <div class="bb-foundation">
-        <a class="bb-foundation-img" href="https://www.dotnetfoundation.org/">
-            <img align="right" src="https://github.com/dotnet-foundation/swag/blob/main/logo/dotnetfoundation_v4.png?raw=true" width="100" />
+        <a class="bb-foundation-img d-none d-sm-block" href="https://www.dotnetfoundation.org/">
+            <img src="./images/dotnet_foundation_v4.png" width="100" />
         </a>
         <div class="bb-foundation-content">本项目属于 <a href="https://www.dotnetfoundation.org/">.NET 基金会</a>，并根据其 <a href="https://www.dotnetfoundation.org/code-of-conduct">行为准则</a> 运作。</div>
     </div>