set default_codec doc attribute

Author: jsvd

CHANGELOG.md

@@ -1,3 +1,6 @@
+## 8.0.5
+  - Docs: Set the default_codec doc attribute.
+
 ## 8.0.4
   - Upgrade Kafka client to version 1.0.0
 

docs/index.asciidoc

@@ -1,5 +1,6 @@
 :plugin: kafka
 :type: input
+:default_codec: plain
 
 ///////////////////////////////////////////
 START - GENERATED VARIABLES, DO NOT EDIT!
@@ -541,3 +542,5 @@ Java Class used to deserialize the record's value
 
 [id="plugins-{type}s-{plugin}-common-options"]
 include::{include_path}/{type}.asciidoc[]
+
+:default_codec!:

logstash-input-kafka.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name            = 'logstash-input-kafka'
-  s.version         = '8.0.4'
+  s.version         = '8.0.5'
   s.licenses        = ['Apache License (2.0)']
   s.summary         = "Reads events from a Kafka topic"
   s.description     = "This gem is a Logstash plugin required to be installed on top of the Logstash core pipeline using $LS_HOME/bin/logstash-plugin install gemname. This gem is not a stand-alone program"