Introduce instrumentation tests

app/test/build.gradle.kts

@@ -0,0 +1,24 @@
+plugins {
+    id("com.android.application")
+    kotlin("android")
+}
+
+android {
+    namespace = "com.topjohnwu.magisk.test"
+
+    defaultConfig {
+        applicationId = "com.topjohnwu.magisk.test"
+        versionCode = 1
+        versionName = "1.0"
+    }
+}
+
+setupAppCommon()
+
+dependencies {
+    compileOnly(project(":app:core"))
+
+    implementation(libs.test.runner)
+    implementation(libs.test.rules)
+    implementation(libs.test.junit)
+}