Improve packaging of published jars

- Publish javadoc again: for now this is just the common-api

 - Remove all dependencies from the published Forge jar. This is
   technically not needed (fg.deobf does this anyway), but seems
   sensible.

projects/forge-api/build.gradle.kts

@@ -16,3 +16,11 @@ dependencies {
 tasks.javadoc {
     include("dan200/computercraft/api/**/*.java")
 }
+
+publishing {
+    publications {
+        named("maven", MavenPublication::class) {
+            fg.component(this)
+        }
+    }
+}