Update Dockerfiles to use ubi9 image in place of ubi8

[kevchu3]

This pull request makes the following changes:

• Update Dockerfiles to use Red Hat ubi9 image instead of ubi8. The latest ubi8 image has some package issues affecting the Dockerfiles using it, see errors below:

$ podman build -f Dockerfile .

...
STEP 14/19: RUN microdnf remove -y gzip shadow-utils

(microdnf:1): librhsm-WARNING **: 19:15:45.242: Found 0 entitlement certificates

(microdnf:1): librhsm-WARNING **: 19:15:45.242: Found 0 entitlement certificates
error: Could not depsolve transaction; 1 problem detected:
 Problem: package cracklib-2.9.6-15.el8.x86_64 from @System requires gzip, but none of the providers can be installed
  - conflicting requests
  - problem with installed package cracklib-2.9.6-15.el8.x86_64
Error: building at STEP "RUN microdnf remove -y gzip shadow-utils": while running runtime: exit status 1

This is not an issue in the ubi9 image which builds successfully. I understand that there are a lot more changes and dependencies that go into ubi9, and hopefully this PR gets the ball rolling with that conversation.