Fix subgroup repository disappearance if group was moved

What does this MR do?

Update Namespace method respository_storage_path to include projects from subgroups

Are there points in the code the reviewer needs to double check?

no

Why was this MR needed?

Fixes issue: "Changing group name with subgroups causes repository disappearance"

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/30261. Part of https://gitlab.com/gitlab-org/gitlab-ce/issues/2772

added 1 commit

• a7fdf4c6 - Fix subgroup repository disappearance if group was moved

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marked as a Work In Progress

marked the task Added for this feature/bug as completed

marked the task Conform by the style guides as completed

marked the task Branch has no merge conflicts with master (if it does - rebase it please) as completed

marked the task Squashed related commits together as completed

marked the task All builds are passing as completed

marked the task Changelog entry added, if necessary as completed

unmarked as a Work In Progress

@DouweM please review

assigned to @DouweM

@dzaporozhets I don't know if this is related, but there is a 500 error in the MRs, see my comments from https://gitlab.com/gitlab-com/infrastructure/issues/1468#note_26726953 and below.

assigned to @dzaporozhets

@DouweM I added method to namespace model and extended https://gitlab.com/gitlab-org/gitlab-ce/issues/2772 with improvements mentioned in https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/10414#note_26812646

The reason I want to keep this MR only about fixing data loss bug so it can be picked into next patch release

resolved all discussions

added 1 commit

• f0fde37b - Fix subgroup repository disappearance if group was moved

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added 172 commits

• f0fde37b...65ea732c - 171 commits from branch master
• 0617876d - Fix subgroup repository disappearance if group was moved

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@DouweM please review and mark for merge if ok

assigned to @DouweM

added ~149423 label

merged

mentioned in commit 271ab515

Picked into 9-1-stable, will go into 9.1-RC1

removed ~149423 label

mentioned in commit 65b04fdb

mentioned in issue #30235 (closed)

mentioned in issue #29718 (closed)