Fixed autocomplete for the case where search string gives nothing on a file search

src/shell/autocomplete.rs

@@ -189,8 +189,7 @@ fn autocomplete_file(search: &Search) -> std::io::Result<(String, String)> {
     }
 
     if nbr_found == 0 {
-        let ret_val = format!("{}{}", &search.command, &search.searchee);
-        return Ok((ret_val, String::new()));
+        *&mut last_found = search.searchee.clone();
     }
 
     //Handle the path when tabbing in a long path, zsh-like