rhel8.3: Update release date
Per https://www.redhat.com/en/about/press-releases/latest-version-red-hat-enterprise-linux-8-extends-linux-foundation-digital-transformation Release notes at https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html-single/8.3_release_notes/index
Signed-off-by: Felipe Borges felipeborges@gnome.org