Update tenant token api for v0.28.1

[bidoubiwa]

All Changes

• apiKeyPrefix claim is now named apiKeyUid and expects the uid of the signing API key as a value.

Breaking Changes

The payload of the tenant token is now using the new uid field of a key, instead of the key itself:

Example:

 let api_key_uid = "76cf8b87-fd12-4688-ad34-260d930ca4f4".to_string();
 let key = "Ëa1ทt9bVcL-vãUทtP3OpXW5qPc%bWH5ทvw09";
 let token = generate_tenant_token(api_key_uid.clone(), json!(SEARCH_RULES), key, None).unwrap();