Raise the minimum supported version of AsciidoctorJ to 2.5

Closes gh-751

Author: wilkinsona

docs/src/docs/asciidoc/getting-started.adoc

@@ -106,7 +106,7 @@ the configuration are described in the following listings:
 			<plugin> <2>
 				<groupId>org.asciidoctor</groupId>
 				<artifactId>asciidoctor-maven-plugin</artifactId>
-				<version>1.5.8</version>
+				<version>2.2.1</version>
 				<executions>
 					<execution>
 						<id>generate-docs</id>

gradle.properties

@@ -13,4 +13,5 @@ asciidoctorj24Version=2.4.3
 asciidoctorj25Version=2.5.1
 
 javaFormatVersion=0.0.27
+
 jmustacheVersion=1.12

samples/rest-notes-spring-data-rest/pom.xml

@@ -83,7 +83,7 @@
 			<plugin>
 				<groupId>org.asciidoctor</groupId>
 				<artifactId>asciidoctor-maven-plugin</artifactId>
-				<version>1.5.8</version>
+				<version>2.2.1</version>
 				<executions>
 					<execution>
 						<id>generate-docs</id>
@@ -96,9 +96,6 @@
 							<doctype>book</doctype>
 							<logHandler>
 								<outputToConsole>true</outputToConsole>
-								<failIf>
-									<severity>DEBUG</severity>
-								</failIf>
 							</logHandler>
 						</configuration>
 					</execution>

settings.gradle

@@ -36,10 +36,6 @@ settings.gradle.projectsLoaded {
 
 include "docs"
 include "spring-restdocs-asciidoctor"
-include "spring-restdocs-asciidoctor-1.5"
-include "spring-restdocs-asciidoctor-1.6"
-include "spring-restdocs-asciidoctor-2.x"
-include "spring-restdocs-asciidoctor-support"
 include "spring-restdocs-core"
 include "spring-restdocs-mockmvc"
 include "spring-restdocs-platform"