Excavator: Upgrades gradle wrapper to the latest version (apache-spark-on-k8s#480)

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Changes produced by the roomba/latest-gradle-wrapper-oss check.

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Author: svc-excavator-bot

build.gradle

@@ -26,7 +26,7 @@ buildscript {
     classpath 'com.palantir.baseline:gradle-baseline-java:0.41.0'
     classpath 'com.palantir.gradle.gitversion:gradle-git-version:0.11.0'
     classpath 'com.jfrog.bintray.gradle:gradle-bintray-plugin:1.8.4'
-    classpath 'com.netflix.nebula:nebula-publishing-plugin:9.2.0'
+    classpath 'com.netflix.nebula:nebula-publishing-plugin:9.5.0'
   }
 }
 

gradle/wrapper/gradle-wrapper.jar

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.0-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.2.1-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists