fix: skins/themes save buttons. remove material icons from header

src/views/admin/appearance/skins.tpl

@@ -5,7 +5,7 @@
 
 	<div data-type="bootswatch" data-theme="" data-css="">
 		<button data-action="use" class="btn btn-primary position-fixed bottom-0 end-0 px-3 py-2 mb-4 me-4 rounded-circle fs-4" type="button" style="width: 64px; height: 64px;">
-			<i class="material-icons">undo</i>
+			<i class="fa fa-fw fas fa-rotate-left"></i>
 		</button>
 	</div>
 </div>

src/views/admin/appearance/themes.tpl

@@ -5,5 +5,5 @@
 </div>
 
 <button id="revert_theme" class="btn btn-primary position-fixed bottom-0 end-0 px-3 py-2 mb-4 me-4 rounded-circle fs-4" type="button" style="width: 64px; height: 64px;">
-	<i class="material-icons">undo</i>
+	<i class="fa fa-fw fas fa-rotate-left"></i>
 </button>

src/views/admin/header.tpl

@@ -6,7 +6,6 @@
 		{{{each metaTags}}}{function.buildMetaTag}{{{end}}}
 		{{{each linkTags}}}{function.buildLinkTag}{{{end}}}
 		<link rel="stylesheet" type="text/css" href="{relative_path}/assets/admin.css?{cache-buster}" />
-		<link rel="stylesheet" href="https://fonts.googleapis.com/icon?family=Material+Icons">
 
 		<script>
 			var config = JSON.parse('{{configJSON}}');