Add requirements for OIDC SSO

[rjmidau]

Resolves #769

New Behavior

Extends requirements to enable the use of OpenID Connect SSO Providers from Python Social Auth.

Contrast to Current Behavior

Currently these dependencies aren't included, meaning users can't take advantage of OIDC SSO unless they create their own image.

Discussion: Benefits and Drawbacks

• Benefit: Enabling users to use functionality included in Netbox without needing to create bespoke images.
• Drawback: Additional dependencies increase the image size, and the version pinning will need to be periodically reviewed
• Backwards-compatible: Yes

Changes to the Wiki

None

Proposed Release Note Entry

Requirements needed to use OpenID Connect SSO Providers have been added

Double Check

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