This PR is purposed to fix the tensorflow load error in python 3.9/3.10.
Currently nnabla does not support tensorflow 2.15 or newer version. So we add the upper limitation again to keep it stable and will try to support newer tensorflow in the future.
This PR is purposed to fix the tensorflow load error in python 3.9/3.10. Currently nnabla does not support tensorflow 2.15 or newer version. So we add the upper limitation again to keep it stable and will try to support newer tensorflow in the future.