[clang-tools-extra] [clangd] SelectionTree marks nodes as complete only if children are complete (PR #82237)

[kadir çetinkaya via cfe-commits]

https://github.com/kadircet requested changes to this pull request.

mentioned this offline already but putting in here as well for my sanity.

the patch is missing the actual changes to the logic, it only has test changes.

https://github.com/llvm/llvm-project/pull/82237