Issue #313: allow checking pending invoices (#493)

* Update deprecated datetime

* Add options to Invoices cli
With these options, we are able to return:
1) all invoices (this is the default);
2) pending invoices (paid False, out False);
3) paid invoices;
4) and unpaid invoices.

* make format

* Fix mypy error with datetime

* sort imports

* Remove unneeded unit when printing out info

* Fix wrong method doc

* Try to mint pending invoices

* make pre-commit

* Refactor --tests flag to --mint
The default will be false, i.e., if the user does not
pass in the --mint flag, it will not try to mint
the pending invoice.

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Co-authored-by: callebtc <93376500+callebtc@users.noreply.github.com>

tests/test_mint_lightning_blink.py

@@ -4,7 +4,7 @@ from httpx import Response
 
 from cashu.core.base import Amount, MeltQuote, Unit
 from cashu.core.settings import settings
-from cashu.lightning.blink import MINIMUM_FEE_MSAT, BlinkWallet
+from cashu.lightning.blink import MINIMUM_FEE_MSAT, BlinkWallet  # type: ignore
 
 settings.mint_blink_key = "123"
 blink = BlinkWallet(unit=Unit.sat)