Update MDK with new output from mod generator

Author: neoforge-mdk-automation[bot]

gradle.properties

@@ -18,9 +18,9 @@ minecraft_version=1.21.5
 # as they do not follow standard versioning conventions.
 minecraft_version_range=[1.21.5]
 # The Neo version must agree with the Minecraft version to get a valid artifact
-neo_version=21.5.80
+neo_version=21.5.81
 # The Neo version range can use any version of Neo as bounds
-neo_version_range=[21.5.80,)
+neo_version_range=[21.5.81,)
 
 ## Mod Properties