Wait for SMTP queue agent registration

contrib/testing/smtp-required-tls-check.py

@@ -29,6 +29,7 @@ from pathlib import Path
 
 TOKEN = f"smtp08-{os.getpid()}-{int(time.time())}"
 TIMEOUT = float(os.environ.get("BONGO_TEST_TIMEOUT", "60"))
+STARTUP_SETTLE = float(os.environ.get("BONGO_TEST_STARTUP_SETTLE", "3"))
 INTERNAL_HOST = os.environ.get("BONGO_TEST_INTERNAL_HOST", "")
 INTERNAL_PORT = int(os.environ.get("BONGO_TEST_INTERNAL_PORT", "26"))
 TEMPORARY_PUBLIC_PORT = int(
@@ -505,6 +506,7 @@ def replace_configuration(configuration: dict) -> None:
 def restart_bongo() -> None:
     run([SMTP07.SYSTEMCTL, "restart", "bongo.service"])
     SMTP07.wait_for_bongo()
+    time.sleep(STARTUP_SETTLE)
 
 
 def perform_test() -> None:
@@ -567,6 +569,7 @@ def perform_test() -> None:
             servers, CAPTURES = start_servers(upstream, tls_context)
             run([SMTP07.SYSTEMCTL, "start", "bongo.service"])
             SMTP07.wait_for_bongo()
+            time.sleep(STARTUP_SETTLE)
             validate_global_required()
             SMTP07.cleanup_queue()