fix(deps): update dependency net.minecraftforge:forge to v1.21-51.0.3

Author: renovate[bot]

gradle.properties

@@ -4,7 +4,7 @@ org.gradle.jvmargs=-Xmx3G
 org.gradle.daemon=false
 
 minecraft_version=1.18.2
-forge_version=1.18.2-40.1.80
+forge_version=1.21-51.0.3
 parchment_version=2022.09.04-1.18.2
 jei_version=1.18.2:9.7.2.264
 top_version=3965688