Rewrite plugin, use filenames in lockfile

fixtures/projects/settings/dependency-resolution-management/kotlin/settings.gradle.kts

@@ -0,0 +1,9 @@
+dependencyResolutionManagement {
+    repositories {
+        maven {
+            url = uri(System.getProperty("org.nixos.gradle2nix.m2"))
+            isAllowInsecureProtocol = true
+        }
+    }
+    repositoriesMode.set(RepositoriesMode.PREFER_SETTINGS)
+}