Revert "feat: support <svelte:html> (#2599)" (#2826)

This reverts commit cd1758b.

Author: Rich-Harris

packages/language-server/src/plugins/html/dataProvider.ts

@@ -270,12 +270,6 @@ const svelteTags: ITagData[] = [
             }
         ]
     },
-    {
-        name: 'svelte:html',
-        description:
-            'This element allows you to add properties and listeners to events on `document.documentElement`. This is useful for attributes such as `lang` which influence how the browser interprets the content.',
-        attributes: []
-    },
     {
         name: 'svelte:document',
         description:

packages/svelte2tsx/src/htmlxtojsx_v2/index.ts

@@ -306,7 +306,6 @@ export function convertHtmlxToJsx(
                     case 'Title':
                     case 'Document':
                     case 'Body':
-                    case 'SvelteHTML':
                     case 'SvelteBoundary':
                     case 'Slot':
                     case 'SlotTemplate':
@@ -475,7 +474,6 @@ export function convertHtmlxToJsx(
                     case 'Head':
                     case 'Title':
                     case 'Body':
-                    case 'SvelteHTML':
                     case 'SvelteBoundary':
                     case 'Document':
                     case 'Slot':