Test/mint_add_verification_balance (#373)

* add verification balance

* verify input and outputs amounts before flow

* adjust tests

tests/conftest.py

@@ -60,7 +60,7 @@ async def ledger():
             await ledger.load_used_proofs()
         await ledger.init_keysets()
 
-    database_name = "test"
+    database_name = "mint"
 
     if not settings.mint_database.startswith("postgres"):
         # clear sqlite database