Replace jcenter() with mavenCentral(). Ignore .kotlin folder

Author: tuancoltech

.gitignore

@@ -73,3 +73,6 @@ lint/generated/
 lint/outputs/
 lint/tmp/
 # lint/reports/
+
+# Kotlin
+.kotlin/

build.gradle

@@ -2,7 +2,7 @@
 buildscript {
     repositories {
         google()
-        jcenter()
+        mavenCentral()
     }
     dependencies {
         classpath 'com.android.tools.build:gradle:8.8.1'
@@ -15,7 +15,7 @@ buildscript {
 allprojects {
     repositories {
         google()
-        jcenter()
+        mavenCentral()
         maven {
             url "https://jitpack.io"
         }