Bump net.minecraftforge.gradle from 5.1.+ to 6.0.16

Bumps net.minecraftforge.gradle from 5.1.+ to 6.0.16.

---
updated-dependencies:
- dependency-name: net.minecraftforge.gradle
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

settings.gradle

@@ -20,7 +20,7 @@ pluginManagement {
 		gradlePluginPortal()
 	}
 	plugins {
-		id "net.minecraftforge.gradle" version "5.1.+"
+		id "net.minecraftforge.gradle" version "6.0.+"
 		id "org.parchmentmc.librarian.forgegradle" version "1.+"
 		id "org.spongepowered.mixin" version "0.7.+"