Renovate: Update mattermost/mattermost-team-edition Docker tag to v5.34.2

Renovate has identified updated artifacts for this project. The main resouce in this project does not have a Renovate Datasource to update it. Updates are tracked using an alternative method and therefore does not have a MR aleady created. This issue requires you to verify that this updated version exists at the resource upstream, create a MR with the updated values, and relate the this issue to that MR.

If Issue is not applicable

• Will not do, this version is not applicable

Steps:

• MR created
• MR related to this issue

Definition of Done:

• Merge topic branch into development
• Merge development into master

If this update produces new findings, perform the following (use this ticket instead of creating a new one):

• Assign label Container::New Findings
• Submit justifications and start approval process.