Rename Credential property `rawId` into `id`

[Spomky]

Description

Version 4.9.x deprecates $id (base64) in favor of $rawId (binary). $id will be removed in 5.0.0. In 5.1.x, $rawId will be deprecated in favor of $id, which will contain exactly the same value as $rawId. This way, in 6.0.0, only the binary version in $id will exist.

Example

No response

[Spomky]

See #581 and #589