finance/py-stripe: Update to 1.29.1, Modernize

• Update PORTVERSION and distinfo checksum (1.29.1)
• Add LICENSE_FILE
• Update TEST depends and test target
• Update test target environment variable [1]
• Remove TESTS option bits accordingly
• Patch setup.py tests_require to allow the latest version of mock [2]
• Remove patch to setup.py:package_data (upstreamed) [3]

Changes:

https://github.com/stripe/stripe-python/blob/v1.29.1/CHANGELOG

[1] https://github.com/stripe/stripe-python/issues/172
[2] https://github.com/stripe/stripe-python/issues/205
[3] https://github.com/stripe/stripe-python/pull/170