Fix rockylinux8-java8 arm64 hash (#2920)

"Test on Rocky Linux 8 (arm64)" in bazel-release.yml pulls the amd
image, thus failing.

This is an addendum to
https://github.com/bazelbuild/continuous-integration/pull/2918. The
culprit is
https://github.com/bazelbuild/continuous-integration/pull/2909