Revert "[modern] Fix broken rendering of `main` and `dialog` elements in IE9-11"

This reverts commit 3926ffa8ca.

Reason for revert: After consideration of the new task T256520 this shipping a normalize CSS feature seems like a much better approach
to solving this problem, particularly since `template` and `dialog`
are unused in our code.

Change-Id: I20391cc6c1f5a50127cd84bd7c0f17a20ab92528

bundlesize.config.json

@@ -5,7 +5,7 @@
 	},
 	{
 		"resourceModule": "skins.vector.styles",
-		"maxSize": "8.2 kB"
+		"maxSize": "8.1 kB"
 	},
 	{
 		"resourceModule": "skins.vector.icons",

skin.json

@@ -52,7 +52,7 @@
 		},
 		"skins.vector.styles": {
 			"class": "ResourceLoaderSkinModule",
-			"features": [ "html5", "elements", "content", "interface", "legacy" ],
+			"features": [ "elements", "content", "interface", "legacy" ],
 			"targets": [
 				"desktop",
 				"mobile"