Fix command in README for running the project

Author: Hog185

README.md

@@ -29,7 +29,7 @@ python3 -m venv venv
 source venv/bin/activate
 pip install briefcase
 ```
-Cloning the project, and running `briefcase dev -r` in the root directory
+Cloning the project, and running `briefcase run -r` in the root directory
 
 ## Contributing