Bump tensorflow from 1.14.0 to 2.5.3 in /scripts

Bumps [tensorflow](https://github.com/tensorflow/tensorflow) from 1.14.0 to 2.5.3.
- [Release notes](https://github.com/tensorflow/tensorflow/releases)
- [Changelog](https://github.com/tensorflow/tensorflow/blob/master/RELEASE.md)
- [Commits](tensorflow/tensorflow@v1.14.0...v2.5.3)

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

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Author: dependabot[bot]

scripts/requirements.txt

@@ -1,6 +1,6 @@
 pytube==9.6.0
 Keras==2.2.4
 numpy==1.16.2
-tensorflow==1.14.0
+tensorflow==2.5.3
 opencv_contrib_python==3.4.2.17
 Pillow==7.0.0