Update version numbers for TensorFlow 2.16.0-rc0
Before merging this PR, please double check that it has correctly updated
`core/public/version.h`, `tools/pip_package/setup.py`, and
`tensorflow/tensorflow.bzl`. Also review the execution notes below:

```
Major: 2 -> 2
Minor: 16 -> 16
Patch: 0 -> 0

WARNING: Below are potentially instances of lingering old version string 
"2.16.0" in source directory "tensorflow/" that are not updated by this script. 
Please check them manually!
tensorflow/tools/pip_package/v2/setup.py:51:2.16.0
tensorflow/tools/pip_package/v2/setup.py:117:2.16.0
tensorflow/tools/pip_package/setup.py:51:2.16.0
tensorflow/tools/pip_package/setup.py:124:2.16.0
tensorflow/tensorflow.bzl:85:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:146:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:438:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:439:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:440:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:441:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:442:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:443:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:444:2.16.0

WARNING: Below are potentially instances of lingering old version string 
"2.16.0" in source directory "tensorflow/" that are not updated by this script. 
Please check them manually!
tensorflow/tools/pip_package/v2/setup.py:51:2.16.0
tensorflow/tools/pip_package/v2/setup.py:117:2.16.0
tensorflow/tools/pip_package/setup.py:51:2.16.0
tensorflow/tools/pip_package/setup.py:124:2.16.0
tensorflow/tensorflow.bzl:85:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:146:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:438:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:439:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:440:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:441:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:442:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:443:2.16.0
tensorflow/lite/tools/versioning/runtime_version.cc:444:2.16.0
```