Automated Changelog Entry for 6.4.9 on 6.4.x (#6309)

Co-authored-by: GitHub Action <41898282+github-actions[bot]@users.noreply.github.com>

Author: blink1073

CHANGELOG.md

@@ -14,6 +14,23 @@ Use `pip install pip --upgrade` to upgrade pip. Check pip version with
 
 <!-- <START NEW CHANGELOG ENTRY> -->
 
+## 6.4.9
+
+([Full Changelog](https://github.com/jupyter/notebook/compare/v6.4.7...6f73a5722615be297f8e434a24c41041437da622))
+
+### Maintenance and upkeep improvements
+
+- Update 6.4.x branch with some missing commits [#6308](https://github.com/jupyter/notebook/pull/6308) ([@kycutler](https://github.com/kycutler))
+- Specify minimum version of nbconvert required [#6286](https://github.com/jupyter/notebook/pull/6286) ([@adamjstewart](https://github.com/adamjstewart))
+
+### Contributors to this release
+
+([GitHub contributors page for this release](https://github.com/jupyter/notebook/graphs/contributors?from=2022-01-12&to=2022-03-14&type=c))
+
+[@adamjstewart](https://github.com/search?q=repo%3Ajupyter%2Fnotebook+involves%3Aadamjstewart+updated%3A2022-01-12..2022-03-14&type=Issues) | [@blink1073](https://github.com/search?q=repo%3Ajupyter%2Fnotebook+involves%3Ablink1073+updated%3A2022-01-12..2022-03-14&type=Issues) | [@github-actions](https://github.com/search?q=repo%3Ajupyter%2Fnotebook+involves%3Agithub-actions+updated%3A2022-01-12..2022-03-14&type=Issues) | [@jtpio](https://github.com/search?q=repo%3Ajupyter%2Fnotebook+involves%3Ajtpio+updated%3A2022-01-12..2022-03-14&type=Issues) | [@kevin-bates](https://github.com/search?q=repo%3Ajupyter%2Fnotebook+involves%3Akevin-bates+updated%3A2022-01-12..2022-03-14&type=Issues) | [@kycutler](https://github.com/search?q=repo%3Ajupyter%2Fnotebook+involves%3Akycutler+updated%3A2022-01-12..2022-03-14&type=Issues) | [@Zsailer](https://github.com/search?q=repo%3Ajupyter%2Fnotebook+involves%3AZsailer+updated%3A2022-01-12..2022-03-14&type=Issues)
+
+<!-- <END NEW CHANGELOG ENTRY> -->
+
 ## 6.4.8
 
 ([Full Changelog](https://github.com/jupyter/notebook/compare/v6.4.7...479902d83a691253e0cff8439a33577e82408317))
@@ -28,8 +45,6 @@ Use `pip install pip --upgrade` to upgrade pip. Check pip version with
 
 [@Vishwajeet0510](https://github.com/search?q=repo%3Ajupyter%2Fnotebook+involves%3AVishwajeet0510+updated%3A2022-01-12..2022-01-25&type=Issues)
 
-<!-- <END NEW CHANGELOG ENTRY> -->
-
 ## 6.4.7
 
 ([Full Changelog](https://github.com/jupyter/notebook/compare/v6.4.6...b77b5e38b8fa1a20150d7fa4d735dbf1c4f00418))