Add support for `GET /api/v2/authorizations?token=` to filter auths by token value (as in Cloud)

[jstirnaman]

Proposal:
Support the ?token= query parameter in GET /api/v2/authorizations requests.
As in InfluxDB Cloud, the parameter should list only the
authorization with the specified token value.

Current behavior:
GET /api/v2/authorizations responds with the list of authorizations after applying other parameters; ignores token=.

Desired behavior:

• Parity with IDPE.
• GET /api/v2/authorizations should respond with a list that contains only the authorization with the specified token property value.

Alternatives considered:
None

Use case:

• Parity with IDPE (Cloud).
• Support for this parameter appears to be the only difference between the IDPE and OSS contracts for the GET /api/v2/authorizations endpoint.