www/py-dj21-drf-yasg: Update to 1.14.0

Notable changes since 1.11.1:

Additions:

• get_security_definitions and get_security_requirements hooks to OpenAPISchemaGenerator
• Added get_summary_and_description and split_summary_from_description extension points to SwaggerAutoSchema to allow for better customisation

Improvements:

• Updated swagger-ui to version 3.21.0
• Updated ReDoc to version 2.0.0-rc.2

Fixes:

• Implicit ref_name collisions will now throw an exception
• RecursiveField will now also work as a child of ListSerializer

Removals:

• The get_summary and get_description methods have been removed

Deprecations:

• Quietly dropped support for the flex validator; it will still work if the library is installed, but the setup.py requirement was removed and the validator will be silently skipped if not installed

https://github.com/axnsan12/drf-yasg/blob/1.14.0/docs/changelog.rst

Approved by: miwi (mentor)
Differential Revision: https://reviews.freebsd.org/D19560