Bump tensorflow from ad6d8cc to 664756e

Bumps [tensorflow](https://github.com/tensorflow/tensorflow) from `ad6d8cc` to `664756e`.
- [Release notes](https://github.com/tensorflow/tensorflow/releases)
- [Commits](tensorflow/tensorflow@ad6d8cc...664756e)

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

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