Ignore link-local addresses in cluster advertisement

[MerlinDMC]

Summary

Ignore link-local class addresses when selecting the IP address to advertise to the cluster.

Ticket Link

Requested by Jason Blais via e-mail

Checklist

• Added or updated unit tests (required for all new features)
• Added API documentation (required for all new APIs)
• All new/modified APIs include changes to the drivers
• Has enterprise changes (please link)
• Has UI changes
• Includes text changes and localization file (.../i18n/en.json) updates
• Touches critical sections of the codebase (auth, upgrade, etc.)

[mattermod]

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[jasonblais]

Thanks @MerlinDMC! Have reached out to devs for review.

[jasonblais]

@MerlinDMC I sent you an email, but including here too for visibility: https://releases.mattermost.com/mattermost-platform-pr/9223/mattermost-enterprise-linux-amd64.tar.gz can be used to test the changes

[jasonblais]

Verified tested, @crspeller this is ready to merge.