Support newest Android Gradle Plugin (#512)

* Update gradle plugin and compliance on dotenv.gradle

* Update gradle plugin from example and minimum gradle support

Example/android/build.gradle

@@ -12,7 +12,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath("com.android.tools.build:gradle:3.5.2")
+        classpath("com.android.tools.build:gradle:4.1.0")
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files

Example/android/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

android/build.gradle

@@ -5,7 +5,7 @@ buildscript {
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.1.4'
+        classpath 'com.android.tools.build:gradle:4.1.0'
     }
 }
 

android/dotenv.gradle

@@ -80,7 +80,7 @@ tasks.whenTaskAdded { task ->
             if (task.name.toLowerCase() == "generate"+envConfigName+"buildconfig") {
                 task.doFirst() {
                     android.applicationVariants.all { variant ->
-                        def variantConfigString = variant.getVariantData().getName()
+                        def variantConfigString = variant.getName()
                         if (envConfigName.contains(variantConfigString.toLowerCase())) {
                             loadDotEnv(envConfigName)
                             project.env.each { k, v ->