Update Gradle wrapper to 7.0 (#1641)

- Replace deprecated jcenter usage to gradlePluginPortal

Author: breskeby

buildSrc/build.gradle

@@ -53,9 +53,8 @@ props.put("elasticsearch", esVersion)
 props.put("build-tools", buildToolsVersion)
 
 repositories {
-    jcenter()
+    gradlePluginPortal()
     mavenCentral()
-
     // For Elasticsearch snapshots.
     if (localRepo) {
         // For some reason the root dirs all point to the buildSrc folder. The local Repo will be one above that.

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.8-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.0-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

qa/build.gradle

@@ -33,7 +33,7 @@ subprojects {
     buildscript {
         boolean localRepo = project.getProperties().containsKey("localRepo")
         repositories {
-            jcenter()
+            gradlePluginPortal()
             mavenCentral()
             if (localRepo) {
                 // For some reason the root dirs all point to the buildSrc folder. The local Repo will be one above that.