- Update to windows RBE docker image, followed by subsequent regenerate
of win RBE toolchain (basically verifying that the README.md for windows
RBE toolchain works well)
- Also move windows docker image from GCR to GAR (which is where our
other testing images already live).
- (cleanup) Move windows RBE docker image to a better location in our
repo.
This PR should be sufficient to demonstrate how we would go about
upgrading the windows RBE build to VS2022 once needed.
Jan Tattermusch