Bump tensorflow from 2.4.0 to 2.4.2

Bumps [tensorflow](https://github.com/tensorflow/tensorflow) from 2.4.0 to 2.4.2.
- [Release notes](https://github.com/tensorflow/tensorflow/releases)
- [Changelog](https://github.com/tensorflow/tensorflow/blob/master/RELEASE.md)
- [Commits](tensorflow/tensorflow@v2.4.0...v2.4.2)

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

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Author: dependabot[bot]

docker_requirements.txt

@@ -23,6 +23,6 @@ fairseq==0.10.2
 pyicu==2.6
 deepcut==0.7.0.0
 h5py==2.10.0
-tensorflow==2.4.0
+tensorflow==2.4.2
 pandas==0.24
 tltk==1.3.8