Update docs and CI to support rabbitmq-external chart

[amitsagtani97]

https://wearezeta.atlassian.net/browse/WPB-5886

As of now, there are multiple prs created for the Mandarin release in the past, which were based on top of rabbitmq integration pr. Each of those prs has some minor changes or other fixes as well. Pulling those changes into one pr, as all the changes together makes the CI green and have the required docs changes to support rabbitmq-external chart.

[supersven]

I think the CI fails (https://github.com/wireapp/wire-server-deploy/actions/runs/6333541868/job/17201813518?pr=655#step:6:1237) due to trying to bundle an older wire-server version, while the rabbitmq-external Helm chart was added pretty recently.

I'd propose to bundle a newer wire-server version in the CI: https://github.com/wireapp/wire-server-deploy/blob/31fcb5e6378c7dae0cf3a1def53ad586b49b671e/offline/ci.sh#L112

[amitsagtani97]

@julialongtin @supersven As of now, we have multiple pull requests created while making a release for Mandarin, this pr has all the required changes at one place. Please review this :)

[supersven]

@julialongtin @supersven As of now, we have multiple pull requests created while making a release for Mandarin, this pr has all the required changes at one place.

Hey @amitsagtani97 :wave:

What's wrong about having small, dedicated PRs? I would prefer them.

If you mixed several topics together, could you please update the title and description of this PR?

[supersven]

@amitsagtani97 The code is looking good now. But, IMHO the commit history should be cleaned up a bit: It would be great if you could squash and reword the commit history such that the try&error commits go away... :smile_cat: