Fix generation of CI build artifacts

build-tools-internal/src/main/groovy/elasticsearch.build-complete.gradle

@@ -10,7 +10,7 @@ import java.nio.file.Files
 
 String buildNumber = System.getenv('BUILD_NUMBER')
 String performanceTest = System.getenv('BUILD_PERFORMANCE_TEST')
-if (buildNumber && performanceTest != null) {
+if (buildNumber && performanceTest == null) {
   File uploadFile = file("build/${buildNumber}.tar.bz2")
   project.gradle.buildFinished { result ->
     println "build complete, generating: $uploadFile"