Update Omnibus Mattermost versions

What does this MR do and why?

Update Omnibus Mattermost versions

Omnibus 16.9 ships with Mattermost 9.4.

Omnibus MR: omnibus-gitlab!7384 (merged)

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assigned to @clemensbeck

changed milestone to %16.10

added docs-only documentation groupdistribution maintenancerefactor typemaintenance labels

	1 Message
	This merge request adds or changes documentation files. A review from the Technical Writing team before you merge is recommended. Reviews can happen after you merge.

Documentation review

The following files require a review from a technical writer:

• doc/integration/mattermost/index.md (Link to current live version)

The review does not need to block merging this merge request. See the:

• Metadata for the *.md files that you've changed. The first few lines of each *.md file identify the stage and group most closely associated with your docs change.
• The Technical Writer assigned for that stage and group.
• Documentation workflows for information on when to assign a merge request for review.

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Generated by Danger

@eread can you please review?

requested review from @eread

approved this merge request

Hi @eread ,

GitLab Bot has added the Technical Writing label because a Technical Writer has approved or merged this MR.

This message was generated automatically. You're welcome to improve it.

added Technical Writing label

merged

mentioned in commit ad94a999

resolved all threads

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