Added alpha tag

Author: Reedyuk

gradle.properties

@@ -29,10 +29,10 @@ firebase-functions.skipIosTests=false
 firebase-config.skipIosTests=false
 
 # Versions:
-firebase-app.version=1.4.3
-firebase-auth.version=1.4.3
-firebase-common.version=1.4.3
-firebase-database.version=1.4.3
-firebase-firestore.version=1.4.3
-firebase-functions.version=1.4.3
-firebase-config.version=1.4.3
+firebase-app.version=1.4.3-alpha
+firebase-auth.version=1.4.3-alpha
+firebase-common.version=1.4.3-alpha
+firebase-database.version=1.4.3-alpha
+firebase-firestore.version=1.4.3-alpha
+firebase-functions.version=1.4.3-alpha
+firebase-config.version=1.4.3-alpha