Rocky9

[dominikl]

• Use dnf instead of yum
• Remove installation of epel-release
• Use policycoreutils-python-utils instead of policycoreutils-python
• Add default WEBSERVER_CONF = nginx
• Use absolute paths in omeroweb-install.sh
• Use official nginx repository to install up-to-date nginx version
• Comment out the default nginx server config (so that the omeroweb config is actually used)
• Replace centos7 examples in README with rocky9

(replaces #94)

[dominikl]

Also tested on RHEL9 VM ome-ci-upgrade. But like the omero-server it only works via port forwarding:
ssh USER@134.36.4.3 -L4080:localhost:4080 -L4064:localhost:4064 then http://localhost:4080/webclient/ .