fix(docs): Fixed WebAuth api endpoint URI in OpenAPI spec

[kmahelona]

The endpoint isn't correct. Django returns a 404 for /account/webauthn, but /account/authenticators/webauthn seems to work.

Submitting Pull Requests

General

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  Examples: "fix(google): Fixed foobar bug", "feat(accounts): Added foobar feature".
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Provider Specifics

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• Make sure unit tests are available.
• Add an entry of your provider in test_settings.py::INSTALLED_APPS and docs/installation.rst::INSTALLED_APPS.
• Add documentation to docs/providers/<provider name>.rst and docs/providers/index.rst Provider Specifics toctree.
• Add an entry to the list of supported providers over at docs/overview.rst.

[coveralls]

coverage: 95.839%. remained the same
when pulling 5a7011e on kmahelona:patch-1
into d6e07b2 on pennersr:main.

[pennersr]

Thanks!