Update tensorboard requirement from ~=2.19.0 to >=2.19,<2.21

Updates the requirements on [tensorboard](https://github.com/tensorflow/tensorboard) to permit the latest version.
- [Release notes](https://github.com/tensorflow/tensorboard/releases)
- [Changelog](https://github.com/tensorflow/tensorboard/blob/master/RELEASE.md)
- [Commits](tensorflow/tensorboard@2.19.0...2.20.0)

---
updated-dependencies:
- dependency-name: tensorboard
  dependency-version: 2.20.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

pyproject.toml

@@ -15,7 +15,7 @@ dependencies = [
   "tyro~=0.9.18",
   "pyyaml~=6.0.2",
   "openfermion~=1.7.0",
-  "tensorboard~=2.19.0",
+  "tensorboard>=2.19,<2.21",
   "standard-imghdr~=3.13.0 ; python_version>='3.13'",
 ]
 requires-python = ">=3.12"