Remove a dependency cycle in the build (elastic/x-pack-elasticsearch#2122)

This is a hack to remove a dependency cycle I added in elastic/x-pack-elasticsearch#2109. I think
it'd be cleaner to remove the cycle by making sql its own plugin that
doesn't depend on the rest of x-pack-elasticsearch but is still
included within x-pack-elasticsearch. But that is a broader change.

Original commit: elastic/x-pack-elasticsearch@47b7d69d80

sql/jdbc/build.gradle

@@ -1,8 +1,6 @@
 import org.elasticsearch.gradle.Version
 import org.elasticsearch.gradle.test.RunTask
 
-apply plugin: 'elasticsearch.build'
-
 description = 'JDBC driver for Elasticsearch'
 
 def generatedResources = "$buildDir/generated-resources/main"

sql/net-client/build.gradle

@@ -1,5 +1,3 @@
-apply plugin: 'elasticsearch.build'
-
 description = 'Common base code for protos'
 
 forbiddenApisMain {

sql/server/build.gradle

@@ -1,7 +1,5 @@
 import org.elasticsearch.gradle.test.RunTask
 
-apply plugin: 'elasticsearch.build'
-
 description = 'The server components of SQL for Elasticsearch'
 
 dependencies {
@@ -31,6 +29,10 @@ compileTestJava.options.compilerArgs << "-parameters"
 // Configure integration tests
 apply plugin: 'elasticsearch.rest-test'
 integTest.mustRunAfter test
+gradle.projectsEvaluated {
+  // Hack to remove a dependency cycle
+  project(':x-pack-elasticsearch:plugin').test.mustRunAfter.getDependencies(project(':x-pack-elasticsearch:plugin').test).remove(test)
+}
 
 integTestCluster {
   distribution = 'zip' // NOCOMMIT make double sure we want all the modules