Use Gradle resolutionStrategy to align asciidoctor plugin versions

* All plugins (convert, pdf, etc) are released together and compatibility
between versions is not guaranteed.
So, this PR uses 'resolutionStrategy' to assign the same version to all
plugins ensuring they are all aligned
* Bump asciidoctor gradle plugins to 4.0.1

settings.gradle

@@ -1,9 +1,16 @@
 pluginManagement {
+	resolutionStrategy {
+		eachPlugin {
+			if (requested.id.namespace?.startsWith('org.asciidoctor.jvm')) {
+				useVersion("4.0.1")
+			}
+		}
+	}
 	plugins {
 		id "io.spring.nohttp" version "0.0.11"
 		id 'org.springframework.boot' version "3.1.5"
-		id 'org.asciidoctor.jvm.pdf' version '3.3.2'
-		id 'org.asciidoctor.jvm.convert' version '3.3.2'
+		id 'org.asciidoctor.jvm.pdf'
+		id 'org.asciidoctor.jvm.convert'
 	}
 	repositories {
 		gradlePluginPortal()

spring-cloud-app-broker-docs/build.gradle

@@ -18,8 +18,8 @@ import org.springframework.boot.gradle.plugin.SpringBootPlugin
 
 plugins {
 	id 'org.springframework.boot' apply false
+	id 'org.asciidoctor.jvm.convert'
 	id 'org.asciidoctor.jvm.pdf'
-  id 'org.asciidoctor.jvm.convert' version '3.3.2'
 }
 
 description = "Spring Cloud App Broker Documentation"