Fix CI log interleaving

* Stop logs from parallel tests interleaving with each other
* Cut down on noise and reduce page load times by only logging std
streams for tests that fail
* @Validated AT cloud foundry configuration
* Remove unnecessary Gradle tasks from the AT job since they've already
been performed as part of `build`
* Stop tests and javadoc Gradle tasks being run against docs subproject
and causing failures

#380

spring-cloud-app-broker-docs/src/docs/asciidoc/index.adoc

@@ -6,7 +6,7 @@
 :toclevels: 4
 :sectlinks:
 
-:examples-dir: ../../src/test/java/com/example/appbroker/
+:examples-dir: ../../src/main/java/com/example/appbroker/
 :sapbr: https://cloud.spring.io/spring-cloud-app-broker/
 :sapbr-href: {sapbr}[Spring Cloud App Broker]
 :sapbr-api: https://docs.spring.io/spring-cloud-app-broker/docs/{project-version}/api/

spring-cloud-app-broker-docs/src/docs/asciidoc/service-bindings.adoc

@@ -1,4 +1,4 @@
-:examples-dir: ../../src/test/java/com/example/appbroker/
+:examples-dir: ../../src/main/java/com/example/appbroker/
 [[service-bindings]]
 == Service Bindings
 

spring-cloud-app-broker-docs/src/docs/asciidoc/service-instances.adoc

@@ -1,4 +1,4 @@
-:examples-dir: ../../src/test/java/com/example/appbroker/
+:examples-dir: ../../src/main/java/com/example/appbroker/
 [[service-instances]]
 == Service Instances