chore(deps): bump tensorflow in /components/kubeflow/dnntrainer/src

Bumps [tensorflow](https://github.com/tensorflow/tensorflow) from 1.15.4 to 2.4.0.
- [Release notes](https://github.com/tensorflow/tensorflow/releases)
- [Changelog](https://github.com/tensorflow/tensorflow/blob/master/RELEASE.md)
- [Commits](tensorflow/tensorflow@v1.15.4...v2.4.0)

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

components/kubeflow/dnntrainer/src/setup.py

@@ -28,7 +28,7 @@
   long_description="""
   """,
   install_requires=[
-    'tensorflow==1.15.4',
+    'tensorflow==2.4.0',
   ],
   package_data={
   },