Highlight "### CHANGED" strings in the debug log of pihole.toml

[DL6ER]

What does this implement/fix?

See title, example:

Related issue or feature (if applicable): N/A

Pull request in docs with documentation (if applicable): N/A

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[yubiuser]

At some point, we may want to check the file line-by-line, so that's the reason for an array

As you decided to remove this possibility, you can remove all the leftovers from file_content

[DL6ER]

@yubiuser I addressed your comment