Use test.systemProperty

Author: prdoyle

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/ElasticsearchTestBasePlugin.java

@@ -298,10 +298,9 @@ private static void configureEntitlements(Project project) {
 
             // Agent
             if (agentFiles.isEmpty() == false) {
-                var systemProperties = test.getExtensions().getByType(SystemPropertyCommandLineArgumentProvider.class);
                 test.getInputs().files(agentFiles);
-                systemProperties.systemProperty("es.entitlement.agentJar", agentFiles.getAsPath());
-                systemProperties.systemProperty("jdk.attach.allowAttachSelf", true);
+                test.systemProperty("es.entitlement.agentJar", agentFiles.getAsPath());
+                test.systemProperty("jdk.attach.allowAttachSelf", true);
             }
 
             // Bridge