Map ROSA Linux to the fedora variant

[mikhailnov]

ROSA is an RPM/dnf-based distro using NetworkManager, but it is not known to cloud-init, so system_info()["variant"] fell back to the generic "linux". As a result templates were rendered with the Debian layout: the systemd generator looked for ds-identify under /usr/lib/cloud-init instead of /usr/libexec/cloud-init, the service units got Debian-specific systemd ordering and the sysconfig network renderer reported itself unavailable.

Map the "rosa" distro id to the existing "fedora" variant so that ROSA reuses the Fedora structure everywhere.

[github-actions]

Hello! Thank you for this proposed change to cloud-init. This pull request is now marked as stale as it has not seen any activity in 14 days. If no activity occurs within the next 7 days, this pull request will automatically close.

If you are waiting for code review and you are seeing this message, apologies! Please reply, tagging blackboxsw, and he will ensure that someone takes a look soon.

(If the pull request is closed and you would like to continue working on it, please do tag blackboxsw to reopen it.)

[blackboxsw]

Thank you for the submision an your intent to improve cloud-init.

If we are adding new distributions such as ROSA support, generally we want to look at something more along the lines of defining a new cloudinit.distro subclass such as the openmadriva example, and adding support for that named distro to cloudinit/config/cloud.cfg.tmpl for downstream packagers to appropriately setup the correct cloud-config modules as part of the default cloud.cfg definitions. Please feel free to resubmit this PR or a separate PR that better aligns with our distro class implementation. We don't want to start making variant derivatives of other derivatives in cloudinit/util.py as it is not easily discoverable.

[github-actions]

Hello! Thank you for this proposed change to cloud-init. This pull request is now marked as stale as it has not seen any activity in 14 days. If no activity occurs within the next 7 days, this pull request will automatically close.

If you are waiting for code review and you are seeing this message, apologies! Please reply, tagging blackboxsw, and he will ensure that someone takes a look soon.

(If the pull request is closed and you would like to continue working on it, please do tag blackboxsw to reopen it.)