doc(Html2Pdf): add Inject service sample code (#8077)

Author: ArgoZhang

src/BootstrapBlazor.Server/Components/Samples/Html2Pdfs.razor

@@ -1,4 +1,4 @@
-@page "/html2pdf"
+@page "/html2pdf"
 
 <h3>@Localizer["Html2PdfTitle"]</h3>
 
@@ -26,6 +26,9 @@
 
 <PackageTips Name="BootstrapBlazor.Html2Pdf" />
 
+<p class="code-label">@((MarkupString)Localizer["Html2PdfStep1"].Value)</p>
+<Pre>services.AddBootstrapBlazorHtml2PdfService();</Pre>
+
 <p class="code-label">常见问题</p>
 
 <p class="code-quest">1. 本地或者发布后无法使用</p>

src/BootstrapBlazor.Server/Locales/en-US.json

@@ -2579,6 +2579,7 @@
     "Html2PdfIntro3": "3. Convert web pages to Pdf using the <code>IHtml2Pdf</code> service instance method <code>PdfStreamFromHtmlAsync</code>",
     "Html2PdfIntro4": "4. <code>IHtml2Pdf</code> Implement service usage <code>PuppeterSharp</code> convert web pages to <code>Pdf</code>, download <code>Chromium</code> runtime when running for the first time, which may be slow under poor network conditions",
     "Html2PdfNote": "If you export too much content, <code>signalR</code> communication interruption may be triggered. Please adjust the <code>HubOptions</code> configuration.",
+    "Html2PdfStep1": "Inject Service",
     "Html2PdfTitle": "Html export to Pdf",
     "PackageIntro": "Component default not implemented <code>IHtml2Pdf</code>, please refer to the package <code>BootstrapBlazor.Html2Pdf</code> package",
     "Tips1": "Introduce",

src/BootstrapBlazor.Server/Locales/zh-CN.json

@@ -2579,6 +2579,7 @@
     "Html2PdfIntro3": "3. 通过 <code>IHtml2Pdf</code> 服务实例方法 <code>PdfStreamFromHtmlAsync</code> 将网页 转化为 <code>Pdf</code>",
     "Html2PdfIntro4": "4. <code>IHtml2Pdf</code> 实现服务使用 <code>PuppeteerSharp</code> 将网页 转化为 <code>Pdf</code>，首次使用时会下载 <code>Chromium</code> 运行时，网络不好的情况下可能会很慢",
     "Html2PdfNote": "如果导出内容过多，可能会触发 <code>signalR</code> 通讯中断问题，请自行调整 <code>HubOptions</code> 配置即可。",
+    "Html2PdfStep1": "注入服务",
     "Html2PdfTitle": "Html 导出为 Pdf",
     "PackageIntro": "组件默认未实现 <code>IHtml2Pdf</code>，请通过引用包 <code>BootstrapBlazor.Html2Pdf</code> 实现",
     "Tips1": "实现原理",