Add Fabric 1.21.8 support

Author: reusteur73

fabric-1.21.6/src/main/resources/fabric.mod.json

@@ -29,6 +29,6 @@
   "depends": {
     "fabricloader": ">=0.16.9",
     "fabric": ">=0.108.0",
-    "minecraft": ["1.21.6","1.21.7"]
+    "minecraft": ["1.21.6","1.21.7", "1.21.8"]
   }
 }