Bump tensorflow from 2.5.2 to 2.5.3 in /server

Bumps [tensorflow](https://github.com/tensorflow/tensorflow) from 2.5.2 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@v2.5.2...v2.5.3)

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

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

Author: dependabot[bot]

server/requirements.txt

@@ -21,6 +21,6 @@ setuptools==57.0.0
 six==1.15.0
 slim-0.1.tar.gz
 sqlitedict==1.7.0
-tensorflow==2.5.2
+tensorflow==2.5.3
 tflite-support==0.2.0
 Werkzeug==2.0.1