docs: Fix command usage example in README

Correct the syntax for command-line arguments in the usage example.

README.md

@@ -33,7 +33,7 @@ cd albatross
 Albatross is a command-line application. Here's how to use it:
 
 ```shell
-go run main.go <launch_monitor_type> <input_csv_file>
+go run main.go <launch_monitor_type> <input_csv_file>
 ```
 
 For example: