docs: fix instructions for disabling systemd-resolved port 53 for fedora (still compatible with Ubuntu)

[LizenzFass78851]

Description

This supplements the instructions for deactivating systemctl resolve port 53 under Fedora, since one of the previous commands only works under Ubuntu (Debian).

Motivation and Context

• Fixes Documentation Error for Fedora Usage #1656
• the own continuation of Updated the instructions to free up port 53 in Fedora #1660
• to keep the documentation (readme.md) regarding disabling port 53, which is used by systemctl-resolve, up to date.

How Has This Been Tested?

I created 4 VMs:

• Fedora 33
• Fedora 42
• Ubuntu 18.04
• Ubuntu 24.04

I tried the instructions for disabling systemd-resolve in all 4 VMs and found that, following the previous instructions, this no longer worked on Fedora 42. However, it did work on the other 3 VMs (as also noted in the linked issue).

After updating the documentation (readme.md), I tried the additions on Fedora 42 (and Fedora 33), port 53 was successfully disabled.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[yubiuser]

I still think all this configurations is better placed in https://docs.pi-hole.net/docker/

[yubiuser]

I'm not sure if we should have instructions how to set Pi-hole as the DNS for the host at all. While this is a valid configurations, the host's DNS will break if Pi-hole is not running.

[LizenzFass78851]

For Ubuntu's netplan, there is already a similar example of how to use Pihole as a system DNS server in the operating system:

docker-pi-hole/README.md

Lines 195 to 209 in ee0d04f

	Once pi-hole is installed, you'll want to configure your clients to use it ([see here](https://discourse.pi-hole.net/t/how-do-i-configure-my-devices-to-use-pi-hole-as-their-dns-server/245)). If you used the symlink above, your docker host will either use whatever is served by DHCP, or whatever static setting you've configured. If you want to explicitly set your docker host's nameservers you can edit the netplan(s) found at `/etc/netplan`, then run `sudo netplan apply`.
	Example netplan:
	```yaml
	network:
	ethernets:
	ens160:
	dhcp4: true
	dhcp4-overrides:
	use-dns: false
	nameservers:
	addresses: [127.0.0.1]
	version: 2
	```

Therefore, the additionall instructions for set Pihole as a DNS server for the operating system for Fedora users.

[yubiuser]

I see where you'e coming from. This is a more general discussion. (I think I meant to suggest to also move the Ubuntu part to the docs). Maybe @pi-hole/docker-maintainers have an opinion

[yubiuser]

Doc PR moving this to the other repo: pi-hole/docs#1266

I thin we can remove the whole section then and only leave a link.

[LizenzFass78851]

I thin we can remove the whole section then and only leave a link.

The pr #1863 to remove the section has been created

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.

[yubiuser]

#1863 has been merged.