Remove archived plugins

- Remove `obsidian-snippet-downloader`
- Remove `obsidian-system-dark-mode`

community-plugins.json

@@ -174,13 +174,6 @@
     "description": "Control the colors and fonts in Minimal Theme.",
     "repo": "kepano/obsidian-minimal-settings"
   },
-  {
-    "id": "obsidian-system-dark-mode",
-    "name": "System Dark Mode",
-    "author": "@kepano",
-    "description": "Automatically use the operating system's setting to switch between light and dark mode.",
-    "repo": "kepano/obsidian-system-dark-mode"
-  },
   {
     "id": "obsidian-discordrpc",
     "name": "Discord Rich Presence",
@@ -3611,13 +3604,6 @@
     "description": "Make single notes instantly available on the web.",
     "repo": "jonstodle/obsius-obsidian-plugin"
   },
-  {
-    "id": "obsidian-snippet-downloader",
-    "name": "Snippet Downloader",
-    "author": "Mara-Li",
-    "description": "A Obsidian's plugin to help to manage CSS snippets (download / update) from repository.",
-    "repo": "Lisandra-dev/obsidian-snippet-downloader"
-  },
   {
     "id": "execute-code",
     "name": "Execute Code",