Update CHANGELOG.md for v0.15.0 (#4590)

---

#### Does this PR need a docs update or release note?

- [ ] ✅ Yes, it's included
- [ ] 🕐 Yes, but in a later PR
- [ ] ⛔ No

#### Type of change

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- [ ] 🌻 Feature
- [ ] 🐛 Bugfix
- [ ] 🗺️ Documentation
- [ ] 🤖 Supportability/Tests
- [ ] 💻 CI/Deployment
- [ ] 🧹 Tech Debt/Cleanup

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- [ ] 💚 E2E

CHANGELOG.md

@@ -7,20 +7,25 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased] (beta)
 
+## [v0.15.0] (beta) - 2023-10-31
+
+### Added
+- Added `corso repo update-passphrase` command to update the passphrase of an existing Corso repository
+- Added Subject and Message preview to channel messages detail entries
+
 ### Fixed
 - SharePoint backup would fail if any site had an empty display name
 - Fix a bug with exports hanging post completion
+- Handle 503 errors in nested OneDrive packages
 
 ### Changed
-- Item Details formatting in Groups and Teams backups.  Pre-release users will need to run new backups to avoid data corruption.
+- Item Details formatting in Groups and Teams backups
 
 ## [v0.14.2] (beta) - 2023-10-17
 
 ### Added
 - Skips graph calls for expired item download URLs.
 - Export operation now shows the stats at the end of the run
-- Added `corso repo update-passphrase --new-passphrase` command to update the passphrase of existing Corso 
-repo.
 
 ### Fixed
 - Catch and report cases where a protected resource is locked out of access.  SDK consumers have a new errs sentinel that allows them to check for this case.