(v3.6.x): Bump org.asciidoctor.jvm.convert from 4.0.2 to 4.0.3

Bumps org.asciidoctor.jvm.convert from 4.0.2 to 4.0.3.

---
updated-dependencies:
- dependency-name: org.asciidoctor.jvm.convert
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

spring-cloud-open-service-broker-docs/build.gradle

@@ -16,7 +16,7 @@
 
 plugins {
 	id 'org.asciidoctor.jvm.pdf'
-  id 'org.asciidoctor.jvm.convert' version '4.0.2'
+  id 'org.asciidoctor.jvm.convert' version '4.0.3'
 }
 
 description = "Spring Cloud Open Service Broker Documentation"