Upgrade to Spring Asciidoctor Extensions 0.4.3.RELEASE

Pick up the workaround for the AsciidoctorJ bug that prevents the
configprops macro's attributes from being parsed. The lack of parsing
meant that the envvar format was being lost and properties were being
written in the canonical form instead.

Closes gh-21794

spring-boot-project/spring-boot-parent/build.gradle

@@ -19,8 +19,8 @@ dependencies {
 		api("com.vaadin.external.google:android-json:0.0.20131108.vaadin1")
 		api("commons-fileupload:commons-fileupload:1.4")
 		api("io.mockk:mockk:1.9.3")
-		api("io.spring.asciidoctor:spring-asciidoctor-extensions-block-switch:0.4.1.RELEASE")
-		api("io.spring.asciidoctor:spring-asciidoctor-extensions-spring-boot:0.4.1.RELEASE")
+		api("io.spring.asciidoctor:spring-asciidoctor-extensions-block-switch:0.4.3.RELEASE")
+		api("io.spring.asciidoctor:spring-asciidoctor-extensions-spring-boot:0.4.3.RELEASE")
 		api("jline:jline:2.11")
 		api("net.java.dev.jna:jna-platform:5.5.0")
 		api("net.sf.jopt-simple:jopt-simple:5.0.4")