Use mavencentral instead of jcenter (#77883)

jcenter is sunset and regular having stability issues. This should
fix our 6.8 branch. We also change our public available plugins
to use mavencentral instead of jcenter

Author: breskeby

buildSrc/build.gradle

@@ -109,7 +109,10 @@ jar {
  *****************************************************************************/
 
 repositories {
-  jcenter()
+  mavenCentral()
+  maven {
+    url "https://plugins.gradle.org/m2/"
+  }
 }
 
 dependencies {

buildSrc/src/main/groovy/org/elasticsearch/gradle/BuildPlugin.groovy

@@ -605,7 +605,7 @@ class BuildPlugin implements Plugin<Project> {
             name "elastic"
             url "https://artifacts-no-kpi.elastic.co/maven"
         }
-        repos.jcenter()
+        repos.mavenCentral()
         String luceneVersion = VersionProperties.lucene
         if (luceneVersion.contains('-snapshot')) {
             // extract the revision number from the version with a regex matcher

buildSrc/src/main/groovy/org/elasticsearch/gradle/vagrant/VagrantTestPlugin.groovy

@@ -158,7 +158,7 @@ class VagrantTestPlugin implements Plugin<Project> {
     private static void configurePackagingArchiveRepositories(Project project) {
         RepositoryHandler repos = project.repositories
 
-        repos.jcenter() // will have releases before 5.0.0
+        repos.mavenCentral() // will have releases before 5.0.0
 
         /* Setup a repository that tries to download from
           https://artifacts.elastic.co/downloads/elasticsearch/[module]-[revision].[ext]

buildSrc/src/testKit/elasticsearch.build/build.gradle

@@ -13,7 +13,7 @@ dependencies {
 }
 
 repositories {
-    jcenter()
+    mavenCentral()
     repositories {
         maven {
             name "local-repo"

buildSrc/src/testKit/jarHell/build.gradle

@@ -12,7 +12,7 @@ ext.licenseFile = file("$buildDir/dummy/license")
 ext.noticeFile = file("$buildDir/dummy/notice")
 
 repositories {
-    jcenter()
+    mavenCentral()
     repositories {
         maven {
             name "local"

buildSrc/src/testKit/testclusters/build.gradle

@@ -16,7 +16,7 @@ allprojects { all ->
                 url "https://s3.amazonaws.com/download.elasticsearch.org/lucenesnapshots/" + luceneSnapshotRevision
             }
         }
-        jcenter()
+        mavenCentral()
     }
 
     if (project == rootProject || project.name == "alpha" || project.name == "bravo") {

buildSrc/src/testKit/testingConventions/build.gradle

@@ -7,7 +7,7 @@ allprojects {
     apply plugin: 'elasticsearch.build'
 
     repositories {
-        jcenter()
+        mavenCentral()
     }
     dependencies {
         testCompile "junit:junit:4.12"

buildSrc/src/testKit/thirdPartyAudit/build.gradle

@@ -17,7 +17,7 @@ repositories {
         name = "local-test"
         url = file("sample_jars/build/testrepo")
     }
-    jcenter()
+    mavenCentral()
 }
 
 configurations.create("forbiddenApisCliJar")