Merge branch '25-improve-check-empty-word' into 'master'

Resolve "Improve check empty word"

Closes #25

See merge request !25

android/gradle.properties

 org.gradle.jvmargs=-Xmx1536M
 android.useAndroidX=true
 android.enableJetifier=true
-app.versionName=0.0.21
-app.versionCode=21
+app.versionName=0.0.22
+app.versionCode=22

lib/utils/random_pick_word.dart

@@ -28,6 +28,9 @@ class RandomPickWord {
       print('Not enough words in list.');
     }
 
+    // Remove empty words
+    wordList.removeWhere((value) => value == '');
+
     // Randomize words list
     wordList.shuffle();