Heron Devs, We are running into issues with the older Python 3.6 that seems to be resolved in more modern versions of Python. To move things forward and get our release working, I'm upgrading to Python 3.8 in our older Docker container flavors.
Much of the work is being done off of Oliver's previous PR to upgrade us to Python 3.9 support. We updated various Pex dependencies (and other python dependencies such as PyYAML). Please review the latest changes in the PR here: https://github.com/apache/incubator-heron/pull/3646 I'm setting the minimum Python in `bazel_configure.sh` to 3.8. Is everyone ok with this change? Some of the key changes: Centos 7 -> Centos8 (Python 3.6 -> Python 3.9) Ubuntu 18.04 (Python 3.6 -> Python 3.8) I didn't really want to update Centos 7 to 8. But I don't think anyone is using it. The Python 3.9 packages did not exist in the older image flavor. I eventually want to upgrade this to Rocky or Alma Linux flavor or maybe even RedHat's UBI image which could also help solve the OpenJDK issue (i.e. ubi8/openjdk-11). But for now I'm trying to do the least amount of changes to get us over the release finish line. I've also cleaned up a lot of the documentation references to older flavors that no longer exist (ubuntu14.04 and debian9).
