[Chore] Fix ledger prompt

Problem: Previous message could be misleading, since
it doesn't wait for the ledger to be connected and visible,
but the specific app to be opened on it.

Solution: Fix the prompt.

baking/src/tezos_baking/wizard_structure.py

@@ -313,7 +313,8 @@ def import_key(self, key_mode_query, ledger_app=None):
                     print("press Ctrl+C to go back to the key import mode selection.")
                     print(
                         color(
-                            "Waiting for the Ledger Device to appear...", color_green
+                            f"Waiting for the Tezos {ledger_app} to be opened...",
+                            color_green,
                         ),
                         end="",
                         flush=True,