chore: updated jcenter to mavenCentral, updated flipper version (#187)

Author: avishayil

Example/android/build.gradle

@@ -9,7 +9,7 @@ buildscript {
     }
     repositories {
         google()
-        jcenter()
+        mavenCentral()
     }
     dependencies {
         classpath("com.android.tools.build:gradle:3.5.3")
@@ -31,7 +31,7 @@ allprojects {
         }
 
         google()
-        jcenter()
+        mavenCentral()
         maven { url 'https://www.jitpack.io' }
     }
 }

Example/android/gradle.properties

@@ -25,4 +25,4 @@ android.useAndroidX=true
 android.enableJetifier=true
 
 # Version of flipper SDK to use with React Native
-FLIPPER_VERSION=0.54.0
+FLIPPER_VERSION=0.129.0

android/build.gradle

@@ -5,7 +5,7 @@ buildscript {
   if (project == rootProject) {
     repositories {
       google()
-      jcenter()
+      mavenCentral()
     }
 
     dependencies {
@@ -45,7 +45,6 @@ android {
 
 repositories {
   mavenCentral()
-  jcenter()
   google()
 
   def found = false