Update app Android gradle scripts to use flutter.versionName and flutter.versionCode (#146604)

Follow up of #146044 and #141417

Minor change to make Gradle buildscripts shorter.

Author: bartekpacia

packages/flutter_tools/templates/app_shared/android-java.tmpl/app/build.gradle.tmpl

@@ -5,24 +5,6 @@ plugins {
     id "dev.flutter.flutter-gradle-plugin"
 }
 
-def localProperties = new Properties()
-def localPropertiesFile = rootProject.file("local.properties")
-if (localPropertiesFile.exists()) {
-    localPropertiesFile.withReader("UTF-8") { reader ->
-        localProperties.load(reader)
-    }
-}
-
-def flutterVersionCode = localProperties.getProperty("flutter.versionCode")
-if (flutterVersionCode == null) {
-    flutterVersionCode = "1"
-}
-
-def flutterVersionName = localProperties.getProperty("flutter.versionName")
-if (flutterVersionName == null) {
-    flutterVersionName = "1.0"
-}
-
 android {
     namespace = "{{androidIdentifier}}"
     compileSdk = flutter.compileSdkVersion
@@ -40,8 +22,8 @@ android {
         // For more information, see: https://docs.flutter.dev/deployment/android#reviewing-the-gradle-build-configuration.
         minSdk = flutter.minSdkVersion
         targetSdk = flutter.targetSdkVersion
-        versionCode = flutterVersionCode.toInteger()
-        versionName = flutterVersionName
+        versionCode = flutter.versionCode
+        versionName = flutter.versionName
     }
 
     buildTypes {

packages/flutter_tools/templates/app_shared/android-kotlin.tmpl/app/build.gradle.tmpl

@@ -5,24 +5,6 @@ plugins {
     id "dev.flutter.flutter-gradle-plugin"
 }
 
-def localProperties = new Properties()
-def localPropertiesFile = rootProject.file("local.properties")
-if (localPropertiesFile.exists()) {
-    localPropertiesFile.withReader("UTF-8") { reader ->
-        localProperties.load(reader)
-    }
-}
-
-def flutterVersionCode = localProperties.getProperty("flutter.versionCode")
-if (flutterVersionCode == null) {
-    flutterVersionCode = "1"
-}
-
-def flutterVersionName = localProperties.getProperty("flutter.versionName")
-if (flutterVersionName == null) {
-    flutterVersionName = "1.0"
-}
-
 android {
     namespace = "{{androidIdentifier}}"
     compileSdk = flutter.compileSdkVersion
@@ -40,8 +22,8 @@ android {
         // For more information, see: https://docs.flutter.dev/deployment/android#reviewing-the-gradle-build-configuration.
         minSdk = flutter.minSdkVersion
         targetSdk = flutter.targetSdkVersion
-        versionCode = flutterVersionCode.toInteger()
-        versionName = flutterVersionName
+        versionCode = flutter.versionCode
+        versionName = flutter.versionName
     }
 
     buildTypes {