netowrk: enable dnsconfd service in installer environment

[rvykydal]

TODO:

• update kickstart tests

[rvykydal]

/build-image

[github-actions]

Images built based on commit 2dac7ac:

• boot.iso: success

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[rvykydal]

/kickstart-test --testtype smoke

[jkonecny12]

Shouldn't this be handled by the dnsconfd directly? Seems to me that they can have their unit conditioned by this option all the time.

Is there a reason why we should be involved?

[rvykydal]

Shouldn't this be handled by the dnsconfd directly? Seems to me that they can have their unit conditioned by this option all the time.

Is there a reason why we should be involved?

Yes, I was thinking the same. I think the reason was the use case where dnsconfd is not enabled in initramfs but should be enabled in installed system. But thinking of it again it would be more futureproof if the enablement would be owned by dnsconfd, for example if there was a (new separate if needed) intiramfs service owned by dnsconfd that would do the same as the shell script in this PR: if rd.net.dns-backend kernel option has dnsconfd value, enable the dnsconfd service on the root system. What do you think @TomasKorbar ?