Tooltip for S3 URI starts with s3://, inconsistent with restic docs

**Describe the bug**
[Restic docs](https://restic.readthedocs.io/en/latest/030_preparing_a_new_repo.html#s3-compatible-storage):

    restic -r s3:https://server:port/bucket_name init

**Backrest screenshot**

![Image](https://github.com/user-attachments/assets/7220af5a-7e0a-451c-b83b-b42aea8dc691)
