Child Test Plan does not collapse when parent collapses

[somenewacc]

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Description of problem

If a second-level test plan has a nested test plan, then when the first-level test plan is collapsed, the second-level test plan won't be collapsed. It's better to see what I mean in the screenshots.

1. Initial conditions. A and B are expanded:
   

2. After A collapses, C stays on screen:
   

3. When you expand A again, C is now on the end of list, B is not collapsed:
   

Version or commit hash (if applicable)

12.4

Steps to Reproduce

1. Create test plans with structure Parent->Child1->Child2.
2. In Search Test Plans tab expand Parent and Child1 test plans.
3. Collapse Parent test plan, Child2 will be still on the list.

Actual results

Nested child test plans aren't collapsed when parent is collapsed.

Expected results

Nested child test plans are collapsed when parent is collapsed. Or works as hierarchy view on Test Plan page.

Additional info (Python traceback, logs, etc.)

Link to tested plans: https://public.tenant.kiwitcms.org/plan/7637/a