Remove unnecessary asciidoc attributes

docs/modules/ROOT/pages/kafka/spring-cloud-stream-binder-kafka.adoc

@@ -2,8 +2,6 @@
 :github-repo: spring-cloud/spring-cloud-stream-binder-kafka
 :github-raw: https://raw.githubusercontent.com/{github-repo}/{github-tag}
 :github-code: https://github.com/{github-repo}/tree/{github-tag}
-:toc: left
-:toclevels: 8
 :nofooter:
 :sectlinks: true
 
@@ -12,8 +10,6 @@
 = Spring Cloud Stream Kafka Binder Reference Guide
 Sabby Anandan, Marius Bogoevici, Eric Bottard, Mark Fisher, Ilayaperumal Gopinathan, Gunnar Hillert, Mark Pollack, Patrick Peralta, Glenn Renfro, Thomas Risberg, Dave Syer, David Turanski, Janne Valkealahti, Benjamin Klein, Henryk Konsek, Gary Russell, Arnaud Jardiné, Soby Chacko
 :doctype: book
-:toc:
-:toclevels: 4
 :source-highlighter: prettify
 :numbered:
 :icons: font

docs/modules/ROOT/pages/pulsar/spring-cloud-stream-binder-pulsar.adoc

@@ -1,5 +1,3 @@
-:toc: left
-:toclevels: 8
 :nofooter:
 :sectlinks: true
 
@@ -7,8 +5,6 @@
 = Spring Cloud Stream Pulsar Binder Reference Guide
 Soby Chacko; Chris Bono; Alexander Preuß; Jay Bryant; Christophe Bornet
 :doctype: book
-:toc:
-:toclevels: 4
 :source-highlighter: prettify
 :numbered:
 :icons: font

docs/modules/ROOT/pages/rabbit/spring-cloud-stream-binder-rabbit.adoc

@@ -2,8 +2,6 @@
 :github-repo: spring-cloud/spring-cloud-stream-binder-rabbit
 :github-raw: https://raw.githubusercontent.com/{github-repo}/{github-tag}
 :github-code: https://github.com/{github-repo}/tree/{github-tag}
-:toc: left
-:toclevels: 8
 :nofooter:
 :sectlinks: true
 
@@ -11,8 +9,6 @@
 = Spring Cloud Stream RabbitMQ Binder Reference Guide
 Sabby Anandan, Marius Bogoevici, Eric Bottard, Mark Fisher, Ilayaperumal Gopinathan, Gunnar Hillert, Mark Pollack, Patrick Peralta, Glenn Renfro, Thomas Risberg, Dave Syer, David Turanski, Janne Valkealahti, Benjamin Klein, Gary Russell, Jay Bryant
 :doctype: book
-:toc:
-:toclevels: 4
 :source-highlighter: prettify
 :numbered:
 :icons: font

docs/modules/ROOT/pages/spring-cloud-stream.adoc

@@ -1,5 +1,3 @@
-:toc: left
-:toclevels: 8
 :nofooter:
 :sectlinks: true