Updates grpc to 1.44.0 to remove local patch needed for grpc to build.
EDIT: there have been changes to how python is found (mostly removing python2 support) and as such the local python-patch we have for grpc needs to be modified.
This time contributing it to upstream (grpc/grpc#28895) so that it'll get added in a newer version!
For anyone that comes across this:
Here is the error itself for why we need the grpc-python.patch file: https://buildkite.com/ray-project/ray-builders-pr/builds/24659#d293616f-225d-41f9-8de2-03780f12b13f/2386-2416
* Update Bazel (to 3.4.1), gRPC, boringssl, absl.
* Always reinstall Bazel if needing to upgrade to a new Bazel version.
* Add patch for properly detecting Windows Python headers when building gRPC.
* Add minimum Bazel version check.
* Update docs with new Bazel version.
