Bump tensorflow from 2.8.1 to 2.9.3

Bumps [tensorflow](https://github.com/tensorflow/tensorflow) from 2.8.1 to 2.9.3.
- [Release notes](https://github.com/tensorflow/tensorflow/releases)
- [Changelog](https://github.com/tensorflow/tensorflow/blob/master/RELEASE.md)
- [Commits](tensorflow/tensorflow@v2.8.1...v2.9.3)

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

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

Author: dependabot[bot]

requirements.txt

@@ -1,5 +1,5 @@
 protobuf==3.20.1
-tensorflow==2.8.1
+tensorflow==2.9.3
 keras
 numpy
 scipy