Bitwarden SecretsManager not working

[nielscil]

Since update 2023.10 it's possible to selfhost the new SecretsManager functionality. However currently this functionality is not available for a custom plan even with the merge of #14. You can assign users to the SecretsManager functionality and open it, but you can't create a project. This is because bitwarden's CustomPlan class doesn't implement the SecretsManager property like e.q. EnterprisePlan and that is used for checking if it's allowed to add projects.

Things we could do:

• Do nothing and accept we don't have SecretsManager functionality.
• Wait if Bitwarden implements it for CustomPlans, but on their site is mentioned that only Enterprise selfhosted customers can use the SecretsManager.
• Switch to the enterprise plan, don't know what for implications that will have on the usages of bitwarden.
• #15