start using kotlin gradle files

build.gradle

@@ -1,26 +0,0 @@
-// Top-level build file where you can add configuration options common to all sub-projects/modules.
-
-buildscript {
-    repositories {
-        google()
-        jcenter()
-
-    }
-    dependencies {
-        classpath "com.android.tools.build:gradle:${Versions.androidBuildToolsVersion}"
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:${Versions.kotlin}"
-        classpath "org.jetbrains.kotlin:kotlin-serialization:${Versions.kotlin}"
-        classpath "com.squareup.sqldelight:gradle-plugin:${Versions.sqlDelight}"
-    }
-}
-
-allprojects {
-    repositories {
-        google()
-        jcenter()
-    }
-}
-
-task clean(type: Delete) {
-    delete rootProject.buildDir
-}

build.gradle.kts

@@ -0,0 +1,27 @@
+// Top-level build file where you can add configuration options common to all sub-projects/modules.
+
+buildscript {
+    repositories {
+        google()
+        jcenter()
+
+    }
+    dependencies {
+        classpath("com.android.tools.build:gradle:${Versions.androidBuildToolsVersion}")
+        classpath(kotlin("gradle-plugin", version = "${Versions.kotlin}"))
+        classpath(kotlin("serialization", version = "${Versions.kotlin}"))
+        classpath("com.squareup.sqldelight:gradle-plugin:${Versions.sqlDelight}")
+    }
+}
+
+allprojects {
+    repositories {
+        google()
+        jcenter()
+    }
+}
+
+tasks.register("clean").configure {
+    delete("build")
+}
+