refactor(BootstrapInputGroupLabel): use DynamicElement unified tag (#6101)

* refactor: 精简代码

* style: 代码格式化

src/BootstrapBlazor/Components/Input/BootstrapInputGroup.razor.scss

@@ -1,4 +1,4 @@
-.input-group {
+.input-group {
     > .datetime-picker,
     > .select,
     > .switch,

src/BootstrapBlazor/Components/Input/BootstrapInputGroupLabel.razor

@@ -1,29 +1,13 @@
 @namespace BootstrapBlazor.Components
 @inherits DisplayBase<string>
 
-@if (IsInputGroupLabel)
-{
-    <div @attributes="@AdditionalAttributes" class="@ClassString" style="@StyleString" required="@Required">
-        @if (ChildContent != null)
-        {
-            @ChildContent
-        }
-        else
-        {
-            <span>@DisplayText</span>
-        }
-    </div>
-}
-else
-{
-    <label @attributes="@AdditionalAttributes" class="@ClassString" style="@StyleString" required="@Required">
-        @if (ChildContent != null)
-        {
-            @ChildContent
-        }
-        else
-        {
-            @DisplayText
-        }
-    </label>
-}
+<DynamicElement @attributes="@AdditionalAttributes" TagName="@TagName" class="@ClassString" style="@StyleString" required="@Required">
+    @if (ChildContent != null)
+    {
+        @ChildContent
+    }
+    else
+    {
+        @DisplayText
+    }
+</DynamicElement>

src/BootstrapBlazor/Components/Input/BootstrapInputGroupLabel.razor.cs

@@ -23,6 +23,8 @@ public partial class BootstrapInputGroupLabel
         .AddClassFromAttributes(AdditionalAttributes)
         .Build();
 
+    private string TagName => IsInputGroupLabel ? "div" : "label";
+
     /// <summary>
     /// 获得/设置 标签宽度 默认 null 未设置自动适应
     /// </summary>