update bintray to 1.8.4 (#102)

Author: qinfchen

build.gradle

@@ -6,7 +6,7 @@ buildscript {
 
     dependencies {
         classpath 'gradle.plugin.com.palantir:gradle-circle-style:1.1.2'
-        classpath 'com.jfrog.bintray.gradle:gradle-bintray-plugin:1.8.3'
+        classpath 'com.jfrog.bintray.gradle:gradle-bintray-plugin:1.8.4'
         classpath 'com.netflix.nebula:gradle-dependency-lock-plugin:5.0.6'
         classpath 'com.netflix.nebula:nebula-dependency-recommender:6.0.0'
         classpath 'com.netflix.nebula:nebula-publishing-plugin:5.1.4'