Update Chinese (Simplified) translation

Co-authored-by: Hosted Weblate <hosted@weblate.org>
Co-authored-by: 大王叫我来巡山 <hamburger2048@users.noreply.hosted.weblate.org>

locales/zh-CN.json

@@ -470,5 +470,6 @@
     "generic_button_save": "保存",
     "generic_button_rss": "RSS",
     "channel_tab_releases_label": "公告",
-    "generic_channels_count_0": "{{count}} 个频道"
+    "generic_channels_count_0": "{{count}} 个频道",
+    "toggle_theme": "切换主题"
 }