[docker] Upgrade numpy version (#20450)

<!-- Please add a reviewer to the assignee section when you create a PR. If you don't have the access to it, we will shortly find a reviewer and assign them to your PR. -->

## Why are these changes needed?

The change in #20374 was interpreted as a file redirect, not a "greater than" by docker (strangely enough, differently than bash interprets it locally). 

<!-- Please give a short summary of the change and the problem this solves. -->

## Related issue number

<!-- For example: "Closes #1234" -->

## Checks

- [ ] I've run `scripts/format.sh` to lint the changes in this PR.
- [ ] I've included any doc changes needed for https://docs.ray.io/en/master/.
- [ ] I've made sure the tests are passing. Note that there might be a few flaky tests, see the recent failures at https://flakey-tests.ray.io/
- Testing Strategy
   - [ ] Unit tests
   - [ ] Release tests
   - [ ] This PR is not tested :(


Co-authored-by: Alex <[email protected]>

docker/base-deps/Dockerfile

@@ -54,7 +54,7 @@ RUN sudo apt-get update -y && sudo apt-get upgrade -y \
  flatbuffers \
  cython==0.29.23 \
  # Necessary for Dataset to work properly.
- numpy>=1.20 \
+ numpy\>=1.20 \
  psutil \
  blist \ 
  # blist is needed for numpy (which is re-installed when ray is installed)