chore: update README.md

Author: nikola2501

README.md

@@ -63,6 +63,7 @@ git config --global pager.diff diffnav
 | <kbd>Ctrl-u</kbd> | Scroll the diff up   |
 | <kbd>e</kbd>      | Toggle the file tree |
 | <kbd>t</kbd>      | Search/go-to file    |
+| <kbd>c</kbd>      | Copy file path       |
 | <kbd>q</kbd>      | Quit                 |
 
 ## Under the hood