remove unnecessary tabbing

Probably there were multiple tabs here before, but now there is only one thing
here, so having tabs makes no sense.

packages/client/src/pages/emojis.vue

@@ -2,7 +2,7 @@
 <MkStickyContainer>
 	<template #header><MkPageHeader :actions="headerActions" :tabs="headerTabs"/></template>
 	<div :class="$style.root">
-		<XCategory v-if="tab === 'category'"/>
+		<XCategory/>
 	</div>
 </MkStickyContainer>
 </template>
@@ -14,8 +14,6 @@ import * as os from '@/os';
 import { i18n } from '@/i18n';
 import { definePageMetadata } from '@/scripts/page-metadata';
 
-const tab = ref('category');
-
 function menu(ev) {
 	os.popupMenu([{
 		icon: 'fas fa-download',