dynamic attach: fix npe, use ";" as separator instead of "," (#917)

Author: zeitlinger

bootstrap/src/main/java/com/grafana/AgentStarted.java

@@ -9,8 +9,8 @@ public class AgentStarted {
   @SuppressWarnings("SystemOut")
   public static void run(String agentArgs) {
     boolean debug = false;
-    if (!agentArgs.isEmpty()) {
-      String[] options = agentArgs.split(",");
+    if (agentArgs != null && !agentArgs.isEmpty()) {
+      String[] options = agentArgs.split(";");
       for (String option : options) {
         String[] keyValue = option.split("=");
         if (keyValue.length == 2) {

smoke-tests/src/test/java/com/grafana/extensions/smoketest/SmokeTest.java

@@ -89,7 +89,7 @@ protected void startTarget(String extraCliArgs) {
                 MountableFile.forHostPath(agentPath), "/opentelemetry-javaagent.jar")
             .withEnv(
                 "JAVA_TOOL_OPTIONS",
-                "-javaagent:/opentelemetry-javaagent.jar=grafana.otel.debug-agent-startup=true,"
+                "-javaagent:/opentelemetry-javaagent.jar=grafana.otel.debug-agent-startup=true;"
                     + extraCliArgs)
             .withEnv("OTEL_BSP_MAX_EXPORT_BATCH", "1")
             .withEnv("OTEL_BSP_SCHEDULE_DELAY", "10")