Remove unnecessary conditional

Author: mark-vieira

buildSrc/src/main/groovy/org/elasticsearch/gradle/BuildPlugin.groovy

@@ -947,14 +947,12 @@ class BuildPlugin implements Plugin<Project> {
                         '-XX:+HeapDumpOnOutOfMemoryError',
                         "-XX:HeapDumpPath=$heapdumpDir"
 
+                jvmArgs System.getProperty('tests.jvm.argline', '').split(" ")
+
                 if (project.runtimeJavaVersion >= JavaVersion.VERSION_1_9) {
                     jvmArgs '--illegal-access=warn'
                 }
 
-                if (System.getProperty('tests.jvm.argline')) {
-                    jvmArgs System.getProperty('tests.jvm.argline').split(" ")
-                }
-
                 if (Boolean.parseBoolean(System.getProperty('tests.asserts', 'true'))) {
                     jvmArgs '-ea', '-esa'
                 }