Fixes#31545
# Checklist for submitter
If some of the following don't apply, delete the relevant line.
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
files](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/guides/committing-changes.md#changes-files)
for more information.
## Testing
- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **Bug Fixes**
* Resolved issues with Single Sign-On (SSO) and Mobile Device Management
(MDM) SSO authentication failures caused by trailing slashes in URLs,
ensuring proper URL formatting and preventing authentication errors.
* **Tests**
* Added tests to verify correct handling of trailing slashes in SSO URLs
and to ensure errors are properly returned for invalid SSO URL
configurations.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
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