[Gradle] Minor: Add return type for ModuleIds.fromDependency

^KT-46198

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/mpp/ModuleIds.kt

@@ -23,7 +23,7 @@ import org.jetbrains.kotlin.project.model.LocalModuleIdentifier
 import org.jetbrains.kotlin.project.model.MavenModuleIdentifier
 
 internal object ModuleIds {
-    fun fromDependency(dependency: Dependency) = when (dependency) {
+    fun fromDependency(dependency: Dependency): ModuleDependencyIdentifier = when (dependency) {
         is ProjectDependency -> idOfRootModule(dependency.dependencyProject)
         else -> ModuleDependencyIdentifier(dependency.group, dependency.name)
     }
@@ -127,4 +127,4 @@ open class MavenPublicationCoordinatesProvider(
     override val version: String by project.provider {
         getPublication()?.version ?: project.version.toString()
     }
-}
+}