Change asciidoctorj version back to 1.6.0-alpha.5
diff --git a/solr/solr-ref-guide/build.gradle b/solr/solr-ref-guide/build.gradle
index 000476f..d153f4d 100644
--- a/solr/solr-ref-guide/build.gradle
+++ b/solr/solr-ref-guide/build.gradle
@@ -45,7 +45,7 @@
     }
 
     dependencies {
-        classpath "org.asciidoctor:asciidoctorj:1.6.2"
+        classpath "org.asciidoctor:asciidoctorj:1.6.0-alpha.5"
         classpath "org.asciidoctor:asciidoctorj-pdf:1.5.0-alpha.16"
     }
 }