Enabling logging for the geode-benchmarks (#128)

The benchmarks we not logging any of the geode logs, they reported "ERROR
StatusLogger No Log4j 2 configuration file found."

I believe this was broken when we switched to having geode-log4j as a separate
module. Adding that module in as a dependency, which reenables standard geode
logging.

geode-benchmarks/build.gradle

@@ -42,10 +42,10 @@ dependencies {
   implementation(project(':harness'))
 
   implementation(group: 'org.apache.geode', name: 'geode-core', version: geodeVersion)
+  runtime(group: 'org.apache.geode', name: 'geode-log4j', version: geodeVersion)
 
   // Required for missing dependency on geode-core.
   runtime(group: 'org.eclipse.jetty', name: 'jetty-webapp', version: '9.4.12.v20180830')
-  runtime(group: 'org.apache.logging.log4j', name: 'log4j-core', version: '2.12.0')
 
   testImplementation(group: 'org.mockito', name: 'mockito-all', version: project.'mockito-all.version')
   testImplementation(group: 'org.assertj', name: 'assertj-core', version: project.'assertj-core.version')