build: switch to modern plugin application layout

Signed-off-by: Harsh Shandilya <me@msfjarvis.dev>

ui/build.gradle

@@ -1,6 +1,8 @@
-apply plugin: 'com.android.application'
-apply plugin: 'kotlin-android'
-apply plugin: 'kotlin-kapt'
+plugins {
+    id 'com.android.application'
+    id 'org.jetbrains.kotlin.android'
+    id 'org.jetbrains.kotlin.kapt'
+}
 
 version wireguardVersionName
 group groupName
@@ -64,7 +66,6 @@ dependencies {
     implementation "androidx.coordinatorlayout:coordinatorlayout:$coordinatorLayoutVersion"
     implementation "androidx.biometric:biometric:$biometricVersion"
     implementation "androidx.core:core-ktx:$coreKtxVersion"
-    implementation "androidx.databinding:databinding-runtime:$agpVersion"
     implementation "androidx.fragment:fragment-ktx:$fragmentVersion"
     implementation "androidx.preference:preference-ktx:$preferenceVersion"
     implementation "androidx.lifecycle:lifecycle-runtime-ktx:$lifecycleRuntimeKtxVersion"