Modernize test-fixture project. (#465)

test-fixture/app/build.gradle

@@ -1,36 +0,0 @@
-apply plugin: 'com.android.application'
-apply plugin: 'kotlin-android'
-
-android {
-    namespace = "com.example.testapp"
-
-    compileSdkVersion 35
-    buildToolsVersion "35.0.0"
-
-    defaultConfig {
-        applicationId "com.example.testapp"
-        minSdkVersion 21
-        targetSdkVersion 35
-        versionCode 1
-        versionName "1.0"
-
-        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
-    }
-
-    compileOptions {
-        sourceCompatibility JavaVersion.VERSION_11
-        targetCompatibility JavaVersion.VERSION_11
-    }
-}
-
-tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).configureEach {
-    compilerOptions {
-        jvmTarget = org.jetbrains.kotlin.gradle.dsl.JvmTarget.JVM_11
-    }
-}
-
-dependencies {
-    implementation 'androidx.appcompat:appcompat:1.7.0'
-    androidTestImplementation 'androidx.test.ext:junit:1.2.1'
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.6.1'
-}

test-fixture/app/build.gradle.kts

@@ -0,0 +1,36 @@
+plugins {
+    id("com.android.application")
+}
+
+android {
+    namespace = "com.example.testapp"
+    compileSdk = 36
+    buildToolsVersion = "36.0.0"
+
+    defaultConfig {
+        applicationId = "com.example.testapp"
+        minSdk = 23
+        targetSdk = 36
+        versionCode = 1
+        versionName = "1.0"
+
+        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+    }
+
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_17
+        targetCompatibility = JavaVersion.VERSION_17
+    }
+}
+
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile>().configureEach {
+    compilerOptions {
+        jvmTarget.set(org.jetbrains.kotlin.gradle.dsl.JvmTarget.JVM_17)
+    }
+}
+
+dependencies {
+    implementation("androidx.appcompat:appcompat:1.7.1")
+    androidTestImplementation("androidx.test.ext:junit:1.3.0")
+    androidTestImplementation("androidx.test.espresso:espresso-core:3.7.0")
+}