Update project files

build.gradle

@@ -1,18 +1,18 @@
 buildscript {
     repositories {
         google()
-        jcenter()
+        mavenCentral()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:4.0.1'
-        classpath 'com.google.gms:google-services:4.3.3'
-        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.3.0'
+        classpath 'com.android.tools.build:gradle:4.2.1'
+        classpath 'com.google.gms:google-services:4.3.8'
+        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.7.0'
     }
 }
 
 allprojects {
     repositories {
         google()
-        jcenter()
+        mavenCentral()
     }
 }