[Docs] Add boot version override appendix (#410)

spring-pulsar-docs/src/main/asciidoc/index.adoc

@@ -44,6 +44,8 @@ In addition to this reference documentation, we recommend a number of other reso
 
 include::version-compatibility.adoc[leveloffset=+2]
 
+include::override-boot-dependencies.adoc[leveloffset=+2]
+
 include::non-ga-versions.adoc[leveloffset=+2]
 
 include::native-image.adoc[leveloffset=+2]

spring-pulsar-docs/src/main/asciidoc/override-boot-dependencies.adoc

@@ -0,0 +1,40 @@
+[appendix]
+[[appendix.override-boot-deps]]
+= Override Spring Boot Dependencies
+
+When using Spring for Apache Pulsar in a Spring Boot application, the Apache Pulsar dependency versions are determined by Spring Boot's dependency management.
+If you wish to use a different version of `pulsar-client-all` or `pulsar-client-reactive-adapter`, you need to override their version used by Spring Boot dependency management; set the `pulsar.version` or `pulsar-reactive.version` property, respectively.
+
+Or, to use a different Spring for Apache Pulsar version with a supported Spring Boot version, set the `spring-pulsar.version` property.
+
+In the following example, snapshot version of the Pulsar clients and Spring Pulsar are being used.
+
+====
+[source, groovy, subs="+attributes", role="secondary"]
+.Gradle
+----
+ext['pulsar.version'] = '3.0.1-SNAPSHOT'
+ext['pulsar-reactive.version'] = '0.3.1-SNAPSHOT'
+ext['spring-pulsar.version'] = '1.0.1-SNAPSHOT'
+
+dependencies {
+    implementation 'org.springframework.boot:spring-boot-starter-pulsar-reactive'
+}
+----
+
+[source, xml, subs="+attributes", role="primary"]
+.Maven
+----
+<properties>
+    <pulsar.version>3.0.1-SNAPSHOT</pulsar.version>
+    <pulsar-reactive.version>0.3.1-SNAPSHOT</pulsar-reactive.version>
+    <spring-pulsar.version>1.0.1-SNAPSHOT</spring-pulsar.version>
+</properties>
+
+<dependency>
+    <groupId>org.springframework.boot</groupId>
+    <artifactId>spring-boot-starter-pulsar-reactive</artifactId>
+</dependency>
+----
+
+====