Update Gradle asciidoctor-gradle-jvm plugin to 4.0.0-alpha.1 (#924)

Author: puneetbehl

plugin/build.gradle

@@ -6,11 +6,7 @@ plugins {
 	id "war"
 	id "idea"
 	id "eclipse"
-	id "org.asciidoctor.jvm.gems"
 	id 'org.asciidoctor.jvm.convert'
-	id "org.asciidoctor.jvm.pdf"
-	id "org.asciidoctor.jvm.epub"
-	id "org.asciidoctor.kindlegen.base"
 	id "io.spring.dependency-management"
 	id 'maven-publish'
 	id 'signing'

plugin/src/docs/introduction/configGroovy.adoc

@@ -20,8 +20,7 @@ grails.plugin.springsecurity.password.algorithm = 'bcrypt'
 
 If your application incorporates the CXF Grails plugin, it's crucial to arrange the dependencies correctly. Place the CXF dependency above the Spring Security plugin within the `dependencies` block, as shown below:
 
-[source,groovy]
-[subs=="attributes"]
+[source,groovy,subs="+attributes"]
 ----
 dependencies {
     implementation 'org.grails.plugins:cxf:3.1.1'

plugin/src/docs/introduction/gettingStarted.adoc

@@ -7,8 +7,7 @@ Getting started with the plugin is simple and efficient. Follow these steps to e
 
 Begin by installing the Spring Security plugin into your Grails project. Add the following dependency to your `build.gradle`:
 
-[source,gradle]
-[subs=="attributes"]
+[source,gradle,subs="+attributes"]
 ----
 implementation 'org.grails.plugins:spring-security-core:{stableversion}'
 ----

plugin/src/docs/introduction/installation.adoc

@@ -17,8 +17,7 @@ Ensure you have the following set up:
 3. Add the Spring Security Core Plugin dependency to the `dependencies` section in your `build.gradle`:
 
 +
-[source,groovy]
-[subs=="attributes"]
+[source,groovy,subs="+attributes"]
 ----
 dependencies {
     // ... other dependencies

plugin/src/docs/tutorials/usingControllerAnnotations.adoc

@@ -10,8 +10,7 @@ $ cd bookstore
 
 ==== 2. "`Install`" the plugin by adding it to build.gradle
 
-[source,groovy]
-[subs="attributes"]
+[source,groovy,sub="+attributes"]
 ----
 dependencies {
    ...

settings.gradle

@@ -11,11 +11,7 @@ pluginManagement {
         id "com.bertramlabs.asset-pipeline" version "4.3.0"
         id "com.github.erdi.webdriver-binaries" version "3.2"
         id "io.spring.dependency-management" version "1.1.3"
-        id "org.asciidoctor.jvm.convert" version "3.3.2"
-        id "org.asciidoctor.kindlegen.base" version "3.2.0"
-        id "org.asciidoctor.jvm.epub" version "3.3.2"
-        id "org.asciidoctor.jvm.pdf" version "3.3.2"
-        id "org.asciidoctor.jvm.gems" version "3.3.2"
+        id "org.asciidoctor.jvm.convert" version "4.0.0-alpha.1"
     }
 }