chore: update Minecraft versions (#533)

Co-authored-by: moddermore-bot[bot] <207009453+moddermore-bot[bot]@users.noreply.github.com>

Author: moddermore-bot[bot]

src/lib/minecraftVersions.json

@@ -97,6 +97,7 @@
     "1.0"
   ],
   "snapshots": [
+    "1.21.9-pre4",
     "1.21.9-pre3",
     "1.21.9-pre2",
     "1.21.9-pre1",