Fix networking fetcher type case

[kubasobon]

Summary of your changes

Fixes nil dereference panic in case the type is not recognized.

Related Issues

Follow-up to https://github.com/elastic/cloudbeat/pull/2269

[mergify[bot]]

This pull request does not have a backport label. Could you fix it @kubasobon? 🙏 To fixup this pull request, you need to add the backport labels for the needed branches, such as:

• backport-v./d./d./d is the label to automatically backport to the 8./d branch. /d is the digit NOTE: backport-skip has been added to this pull request.

[github-actions[bot]]

:bar_chart: Allure Report - :green_heart: No failures were reported.

Result	Count
🟥 Failed	0
🟩 Passed	359
⬜ Skipped	33