fix: bump msgpack from 1.1.1 to 1.2.1 in /packages/bigframes

Bumps [msgpack](https://github.com/msgpack/msgpack-python) from 1.1.1 to 1.2.1.
- [Release notes](https://github.com/msgpack/msgpack-python/releases)
- [Changelog](https://github.com/msgpack/msgpack-python/blob/main/CHANGELOG.md)
- [Commits](msgpack/msgpack-python@v1.1.1...v1.2.1)

---
updated-dependencies:
- dependency-name: msgpack
  dependency-version: 1.2.1
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

packages/bigframes/testing/constraints-3.11.txt

@@ -311,7 +311,7 @@ mlxtend==0.23.4
 more-itertools==10.7.0
 moviepy==1.0.3
 mpmath==1.3.0
-msgpack==1.1.1
+msgpack==1.2.1
 multidict==6.6.3
 multipledispatch==1.0.0
 multiprocess==0.70.16