Try to fix Forge publication.

build.gradle

@@ -3,6 +3,7 @@ plugins {
   id "org.jetbrains.gradle.plugin.idea-ext" version "1.1.7"
   id "com.hypherionmc.modutils.modpublisher" version "2.1.4" apply false
   id "fabric-loom" version "1.5-SNAPSHOT" apply false
+  id "net.minecraftforge.gradle" version "[6.0,6.2)" apply false
 }
 
 sonar {
@@ -18,6 +19,7 @@ sonar {
 subprojects { subproject ->
   def noPublish = subproject.name === "common"
   def isFabric = subproject.name == "fabric"
+  def isForge = subproject.name == "forge"
 
   apply plugin: "java"
   apply plugin: "idea"
@@ -27,6 +29,9 @@ subprojects { subproject ->
   if (isFabric) {
     apply plugin: "fabric-loom"
   }
+  if (isForge) {
+    apply plugin: "net.minecraftforge.gradle"
+  }
 
   java.toolchain.languageVersion = JavaLanguageVersion.of(17)
   java.withSourcesJar()
@@ -187,7 +192,7 @@ subprojects { subproject ->
     setVersion(mod_version)
     setChangelog(changelog_body)
     setVersionType(version_type)
-    setArtifact(isFabric ? remapJar : jar)
+    setArtifact(isFabric ? remapJar : isForge ? project.tasks.jarJar : jar)
     setDisableMalwareScanner(true) // Disable the built in Fractureizer scanner.
     setDisableEmptyJarCheck(true) // Disable check for valid mod metadata entry in artifact, which could possibly mean that the jar is empty.
     setModrinthID(mod_id_kebab)

forge/build.gradle

@@ -1,7 +1,6 @@
 import net.minecraftforge.gradle.userdev.tasks.JarJar
 
 plugins {
-  id "net.minecraftforge.gradle" version "[6.0,6.2)"
   id "org.spongepowered.mixin" version "0.7-SNAPSHOT"
 }
 
@@ -117,6 +116,7 @@ publishing {
   publications {
     gpr(MavenPublication) {
       fg.component(it)
+      artifact project.tasks.jarJar
     }
   }
 }