Fix/python output to log window (#19)

* Shows python outputs in log window

* Remove the copied line

elyra/kfp/bootstrapper.py

@@ -1,4 +1,5 @@
 #
+#
 # Copyright 2018-2023 Elyra Authors
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -482,10 +483,19 @@ def execute(self) -> None:
             run_args = ["python3", python_script]
             if self.parameter_pass_method == "env":
                 self.set_parameters_in_env()
-
+
+            logger.info("----------------------Python logs start----------------------")
             with open(python_script_output, "w") as log_file:
-                subprocess.run(run_args, stdout=log_file, stderr=subprocess.STDOUT, check=True)
-
+                process = subprocess.Popen(run_args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+                for line in iter(process.stdout.readline, b''):
+                    sys.stdout.write(line.decode())
+                    log_file.write(line.decode())
+
+                process.stdout.close()
+                return_code = process.wait()
+                logger.info("----------------------Python logs ends----------------------")
+                if return_code:
+                    raise subprocess.CalledProcessError(return_code, run_args)
             duration = time.time() - t0
             OpUtil.log_operation_info("python script execution completed", duration)