Enhancing Error Handling, errors will not interrupt the execution of subsequent files

[Flanders1914]

Updates The plot_iperf.sh script has been improved for better error handling and modularity: The script now processes each Gnuplot .plt file individually. Execution success or failure for each .plt file is now explicitly logged: Success: Prints a message indicating the file was executed successfully. Error: Prints an error message and logs errors encountered while executing a .plt file to an error.out file in the current directory, without interrupting the execution of subsequent files.