[server] set default branch for BitBucket provider

[trumbitta]

Description

I found mainbranch in the BitBucket API. Here's hoping it is our missing default branch.

I wasn't able to test it because I couldn't figure out how to rebuild the server app 😬 (whereas with Nx I would have known to run nx build server because the commands are always the same for every single project in the repo, no matter the language or framework - see #7334 😇🍊🦄)

Related Issue(s)

Fixes #7325
Fixes #7366

How to test

If anybody's willing to comment here and explain how to rebuild / relaunch the server project to test this, I'll be adding instructions to the README for future reference 🙏

Release Notes

[server] add default branch to BitBucket provider

[iQQBot]

/werft run

👍 started the job as gitpod-build-trumbitta-7325-fork.0

[gtsiolis]

Thanks for contributing, @trumbitta! 🍊

UX works like a charm! 🔮

This will also resolve pinning the default branch on the top of the list, so feel free to include also #7366 in the PR description.

Approving to unblock merging but holding to ask for another pass for the code changes here from @AlexTugarev who recently changed this file in #7251. 🏀

/hold

[roboquat]

LGTM label has been added.

Git tree hash: 707ab904451eacacddfe9a1866ce4c69ae1fe9d0

[roboquat]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: gtsiolis

Associated issue: #7325

The full list of commands accepted by this bot can be found here.

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Needs approval from an approver in each of these files:

• components/server/OWNERS [gtsiolis]

Approvers can indicate their approval by writing /approve in a comment
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[AlexTugarev]

/werft run

👍 started the job as gitpod-build-trumbitta-7325-fork.1

[AlexTugarev]

/hold cancel

Thanks @trumbitta and @gtsiolis! This is great!