Follow-up for https://gitlab.com/gitlab-org/gitlab/-/issues/26261 https://gitlab.com/gitlab-org/gitlab/-/merge_requests/63771 adds basic support for `default_branch` parameter. It currently has a limitation, that repository must be initialized in order to apply the requested branch name. [Based on the suggestion](https://gitlab.com/gitlab-org/gitlab/-/issues/26261#note_598239927) we can define the initial branch even for the empty repository. But gitaly does not support this option yet. ### Proposal 1. Extend `CreateRepository` request with a new option `default_branch` and apply its value as a flag to git init command (`--initial-branch=<default_branch>`) - https://gitlab.com/gitlab-org/gitaly/-/merge_requests/3582 2. Update gitaly client to support `default_branch` and allow to use `default_branch` option separately from `initialize_from_readme`