Revise Artifactory Name (hyperledger#1888)

Revise the artifactory artifact-id so the download name is correct.

Signed-off-by: Danno Ferrin <danno.ferrin@gmail.com>

build.gradle

@@ -578,7 +578,7 @@ publishing {
     distArtifactory(MavenPublication) {
       groupId (version.contains('SNAPSHOT') ? 'SNAPSHOT' : '.')
       version = project.version
-      artifactId = 'besu-distribution'
+      artifactId = 'besu'
       artifact("$buildDir/distributions/besu-${project.version}.zip")
       artifact("$buildDir/distributions/besu-${project.version}.tar.gz") {
         extension = 'tar.gz'