src/init.rs: change doc for get_borg_folder function

src/init.rs

 use std::path::PathBuf;
 use std::process::{exit, Command};
 
-/// Function used to get git folder
+/// Function used to get borg repository folder and results repository only if 
+/// the project is inside a git repository
 pub fn get_borg_folder() -> (PathBuf, PathBuf) {
     let output = Command::new("git")
         .arg("rev-parse")