[cleaner] Skip obfuscation of substrings for hostnames properly

[pmoravec]

Leftover from #3403 / #3496 where match_full_words_only is ignored for hostname mapping due to own get_regex_result method.

Resolves: #3593

---

Please place an 'X' inside each '[]' to confirm you adhere to our Contributor Guidelines

• Is the commit message split over multiple lines and hard-wrapped at 72 characters?
• Is the subject and message clear and concise?
• Does the subject start with [plugin_name] if submitting a plugin patch or a [section_name] if part of the core sosreport code?
• Does the commit contain a Signed-off-by: First Lastname email@example.com?
• Are any related Issues or existing PRs properly referenced via a Closes (Issue) or Resolved (PR) line?
• Are all passwords or private data gathered by this PR obfuscated?

[pmoravec]

Reproducer:

echo "127.0.0.1 port.foo.bar" >> /etc/hosts
sos report -o networking --clean --disable-parsers=ip,mac,username --batch --build
..
A mapping of obfuscated elements is available at
    /var/tmp/sosrehost17-host0-2024-04-09-svawsjc-private_map

Your sosreport has been generated and saved in:
    /var/tmp/sosrehost17-host0-2024-04-09-svawsjc-obfuscated.tar.xz

[packit-as-a-service]

Congratulations! One of the builds has completed. 🍾

You can install the built RPMs by following these steps:

• sudo yum install -y dnf-plugins-core on RHEL 8
• sudo dnf install -y dnf-plugins-core on Fedora
• dnf copr enable packit/sosreport-sos-3593
• And now you can install the packages.

Please note that the RPMs should be used only in a testing environment.