update forge to 47.3.12

gradle.properties

@@ -13,7 +13,7 @@ minecraft_version=1.20.1
 # as they do not follow standard versioning conventions.
 minecraft_version_range=[1.20.1,1.21)
 # The Forge version must agree with the Minecraft version to get a valid artifact
-forge_version=47.2.0
+forge_version=47.3.12
 # The Forge version range can use any version of Forge as bounds or match the loader version range
 forge_version_range=[47,)
 # The loader version range can only use the major version of Forge/FML as bounds