Fix asciidoctor warnings

Invalid references and mismatched nesting blocks

spring-session-docs/src/docs/asciidoc/guides/boot-redis.adoc

@@ -151,6 +151,6 @@ To do so, enter the following into your terminal, being sure to replace `7e8383a
 ----
 	$ redis-cli del spring:session:sessions:7e8383a4-082c-4ffe-a4bc-c40fd3363c5e
 ----
-=====
+====
 
 Now you can visit the application at http://localhost:8080/ and observe that we are no longer authenticated.

spring-session-docs/src/docs/asciidoc/guides/java-jdbc.adoc

@@ -99,7 +99,7 @@ For additional information on how to configure data access related concerns, see
 
 == Java Servlet Container Initialization
 
-Our <<httpsession-spring-configuration,Spring Configuration>> created a Spring bean named `springSessionRepositoryFilter` that implements `Filter`.
+Our <<httpsession-jdbc-spring-configuration,Spring Configuration>> created a Spring bean named `springSessionRepositoryFilter` that implements `Filter`.
 The `springSessionRepositoryFilter` bean is responsible for replacing the `HttpSession` with a custom implementation that is backed by Spring Session.
 
 In order for our `Filter` to do its magic, Spring needs to load our `Config` class.

spring-session-docs/src/docs/asciidoc/guides/java-rest.adoc

@@ -241,7 +241,7 @@ $ curl -v http://localhost:8080/ -u user:password
 
 In the output, you should notice the following:
 
-===
+====
 ----
 HTTP/1.1 200 OK
 ...

spring-session-docs/src/docs/asciidoc/guides/xml-jdbc.adoc

@@ -68,8 +68,8 @@ You must have the following in your pom.xml:
 	<url>https://repo.spring.io/libs-milestone</url>
 </repository>
 ----
-endif::[]
 ====
+endif::[]
 
 // tag::config[]