Fixing preview licence in travis

Author: kevalpatel2106

.travis.yml

@@ -30,13 +30,8 @@ android:
 before_script:
     - chmod +x gradlew      #Grand permissions
 
-install:
-    - echo y | android update sdk -u -a -t tools
-    - echo y | android update sdk -u -a -t platform-tools
-    - echo y | android update sdk -u -a -t build-tools;28.0.0-rc1
-    - echo y | android update sdk -u -a -t android-P
-    - echo y | android update sdk -u -a -t extra-google-m2repository
-    - echo y | android update sdk -u -a -t extra-android-m2repository
+before_install:
+    - yes | sdkmanager build-tools;28.0.0-rc1
 
 script:
     - ./gradlew assembleDebug -PdisablePreDex --stacktrace