Fix signing artifacts (KT-32192)

Broken in f1e3e26e6cd6e38b473ffe1a23b19b68ebb2d11f.

----
> Task :kotlin-reflect:signArchives FAILED
Build time for tasks:
Compiling kotlin: 1.44s (12.33% of total time)
Processing jars: 4.28s (36.75% of total time)
Uncategorized: 5.39s (46.26% of total time)

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':kotlin-reflect:signArchives'.
> Duplicate key Signature kotlin-reflect:jar.asc:asc:
---

 #KT-32192 Fixed

libraries/reflect/build.gradle.kts

@@ -213,7 +213,9 @@ tasks.getByName("check").dependsOn(dexMethodCount)
 
 artifacts {
     listOf(mainJar.name, "runtime", "archives").forEach { configurationName ->
-        add(configurationName, result)
+        add(configurationName, result.outputs.files.singleFile) {
+            builtBy(result)
+        }
     }
 
     add("archives", modularJar)