Replace usages of deprecated ANDROID_HOME with ANDROID_ROOT_SDK.

Bump build tools to 30.0.3.
Update test-fixture dependencies.

test-fixture/app/build.gradle

@@ -4,7 +4,7 @@ apply plugin: 'kotlin-android-extensions'
 
 android {
     compileSdkVersion 30
-    buildToolsVersion "30.0.2"
+    buildToolsVersion "30.0.3"
 
     defaultConfig {
         applicationId "com.example.testapp"
@@ -26,11 +26,11 @@ android {
 
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
-    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
-    implementation 'androidx.appcompat:appcompat:1.1.0'
-    implementation 'androidx.core:core-ktx:1.3.0'
-    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
+    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
+    implementation 'androidx.appcompat:appcompat:1.2.0'
+    implementation 'androidx.core:core-ktx:1.3.2'
+    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
     testImplementation 'junit:junit:4.13'
-    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
+    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
 }

test-fixture/build.gradle

@@ -1,13 +1,13 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.4.0'
+    ext.kotlin_version = '1.4.21'
     repositories {
         google()
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:4.0.1'
+        classpath 'com.android.tools.build:gradle:4.1.1'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
 
         // NOTE: Do not place your application dependencies here; they belong

test-fixture/gradle.properties

@@ -24,17 +24,5 @@ kapt.include.compile.classpath=false
 # Use R8 instead of ProGuard for code shrinking.
 android.enableR8.fullMode=true
 
-# Enable gradle workers
-android.enableGradleWorkers=true
-
 # Enable AndroidX
 android.useAndroidX=true
-
-# Enable rudimentary R class namespacing where each library only contains
-# references to the resources it declares instead of declarations plus all
-# transitive dependency references.
-android.namespacedRClass=true
-
-# Only keep the single relevant constructor for types mentioned in XML files
-# instead of using a parameter wildcard which keeps them all.
-android.useMinimalKeepRules=true

test-fixture/gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.7.1-bin.zip