Fix parsing of PEM and RSA keys

[paulineribeyre]

Fix a bug introduced in 6.0.2 by #52 when using authutils.token.fastapi.access_token:

Traceback (most recent call last):
  File "/env/lib/python3.9/site-packages/authutils/token/fastapi.py", line 90, in getter
    pub_keys = await pub_keys
fastapi.exceptions.HTTPException

This is caused by calling the OrderedDict constructor with a list of dicts instead of a list of tuples.

Fence's /.well-known/jwks endpoint returns:

{
  keys: [
    {
      kid: "<kid>",
      kty: "RSA",
      n: "<key>",
      [...]
    }
  ]
}

while the /jwt/keys endpoint returns the keys in PEM format:

{
  keys: [
    [
      "<kid>",
      "-----BEGIN PUBLIC KEY----- <key> -----END PUBLIC KEY----- ",
    ]
  ]
}

Since version 6.0.2, get_keys_url can return the URL to either endpoint, and access_token was not updated to work with the non-PEM format.

Bug Fixes

• Fix authutils.token.fastapi.access_token to accept both PEM and RSA key formats

[github-actions]

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