Rewrite plugin, use filenames in lockfile

fixtures/projects/buildsrc/plugin-in-buildsrc/kotlin/buildSrc/build.gradle.kts

@@ -0,0 +1,20 @@
+plugins {
+    `kotlin-dsl`
+}
+
+repositories {
+    gradlePluginPortal()
+}
+
+dependencies {
+    implementation("com.gradle.publish:plugin-publish-plugin:1.2.1")
+}
+
+gradlePlugin {
+    plugins {
+        register("apply-plugin-publish") {
+            id = "com.example.apply-plugin-publish"
+            implementationClass = "com.example.ApplyPluginPublishPlugin"
+        }
+    }
+}

fixtures/projects/buildsrc/plugin-in-buildsrc/kotlin/buildSrc/src/main/kotlin/com/example/ApplyPluginPublishPlugin.kt

@@ -0,0 +1,10 @@
+package com.example
+
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+
+open class ApplyPluginPublishPlugin : Plugin<Project> {
+    override fun apply(project: Project) {
+        project.pluginManager.apply("com.gradle.plugin-publish")
+    }
+}