Corrected a mistake in the instructions for setting up the software environment and running the program using Linux.

README.md

@@ -58,7 +58,7 @@ program.
 ```shell
   python3 -m venv venv
   source ./venv/bin/activate
-  python3 -m pip install -r requirement.txt
+  python3 -m pip install -r virtualenv/requirements.txt
   python3 main.py
 ```