[FIX] server: ensure that the error message is flushed

When Odoo intercept the SIGXCPU signal, an error message is written to
the stderr. Unfortunately, if stderr is redirected to a buffered file, the
message will not appear.

odoo/service/server.py

@@ -208,6 +208,7 @@ class ThreadedServer(CommonServer):
             raise KeyboardInterrupt()
         elif sig == signal.SIGXCPU:
             sys.stderr.write("CPU time limit exceeded! Shutting down immediately\n")
+            sys.stderr.flush()
             os._exit(0)
         elif sig == signal.SIGHUP:
             # restart on kill -HUP