Update mlflow requirement from <2.15,>=2.14.1 to >=2.14.1,<2.16 (#1424)

Updates the requirements on [mlflow](https://github.com/mlflow/mlflow) to permit the latest version.
- [Release notes](https://github.com/mlflow/mlflow/releases)
- [Changelog](https://github.com/mlflow/mlflow/blob/master/CHANGELOG.md)
- [Commits](mlflow/mlflow@v2.14.1...v2.15.0)

---
updated-dependencies:
- dependency-name: mlflow
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

setup.py

@@ -53,7 +53,7 @@
 
 install_requires = [
     'mosaicml[libcloud,wandb,oci,gcs,mlflow]>=0.23.4,<0.24',
-    'mlflow>=2.14.1,<2.15',
+    'mlflow>=2.14.1,<2.16',
     'accelerate>=0.25,<0.34',  # for HF inference `device_map`
     'transformers>=4.43.2,<4.44',
     'mosaicml-streaming>=0.8.0,<0.9',