Reject non-ASCII digits in card_number, uuid and cron

[Shaisolaris]

card_number, uuid and cron accepted digits of other scripts, because int() and str.isdecimal() accept them:

>>> validators.card_number("٤٢٤٢٤٢٤٢٤٢٤٢٤٢٤٢")      # Arabic-Indic form of 4242424242424242
True
>>> validators.uuid("٢bc1c94f-0deb-43e9-92a1-4775189ec9f8")
True
>>> validators.cron("٥ * * * *")
True

Found by running each validator on its documented valid example with the ASCII digits replaced by Arabic-Indic digits. ipv4, ipv6, mac_address, iban and the hash validators already reject them.

Each of the three now requires ASCII input before the existing checks (str.isascii(); in cron a small _is_number helper replaces isdecimal()). domain, hostname and url are left alone, since their labels may be internationalized.

Tests: 9 new cases in test_card.py, test_uuid.py and test_cron.py. They fail on master and pass with the change. pytest tests with the crypto-eth-addresses extra installed: 1122 passed (1113 passed and 9 failed on master with the new tests). ruff check and ruff format are clean.