Ensure that starting the JVM in a threaded environment results in the thread being attached as daemon

cmmnbuild_dep_manager/jvm/_manager.py

 import logging
 import os
+import threading
 
 import jpype as jp
 
@@ -53,3 +54,9 @@ class JVMManager:
         # Prevent further startup argument changes.
         if not self.startup_arguments.frozen:
             self.startup_arguments.frozen = True
+
+        # Attach the thread as daemon if not the main thread.
+        # See https://github.com/jpype-project/jpype/issues/1169.
+        if threading.current_thread() is not threading.main_thread():
+            jp.java.lang.Thread.detach()
+            jp.java.lang.Thread.attachAsDaemon()