Adds release notes for 2.13.7 (#10986)

Co-authored-by: Serina Grill <[email protected]>

RELEASE-NOTES.md

@@ -1,5 +1,23 @@
 # Prefect Release Notes
 
+## Release 2.13.7
+
+### Enabling Pydantic V2
+
+In 2.13.5 we released experimental support for Pydantic V2, which made it co-installable via forced install. In this release, we are enabling co-installation by default which will allow you to leverage Pydantic V2 in your flows and tasks. Additionally, you can choose to update to Pydantic V2 on your own timeline as we maintain compatability with V1 within flows and tasks.
+
+See implementation details in the following pull request:
+- https://github.com/PrefectHQ/prefect/pull/10946
+
+### Documentation
+
+- Fix typo in release notes - https://github.com/PrefectHQ/prefect/pull/10950
+
+### Contributors
+- @taljaards
+
+**All changes**: https://github.com/PrefectHQ/prefect/compare/2.13.6...2.13.7
+
 ## Release 2.13.6
 
 ### Specify a default result storage block as a setting