Cannot open hyperlinks in SVGs in Webview

[EFanZh]

This is for #73272.

Steps to reproduce:

1. Install the Graphviz Preview extension (of version 1.3.2 or up).

2. Configure the graphvizPreview.dotPath option if necessary.

3. Create a new document with the following content:

   graph { Example [URL="https://example.com"] }

4. Change the language to “Graphviz (dot)”.

5. Execute “Graphviz: Open Preview to the Side” command.

6. Click the Example text in the preview.

Expect https://example.com to be opened in a browser window.

@mjbvz