[clang] [clang-tools-extra] [clang][modules] Do not resolve `HeaderFileInfo` externally in `ASTWriter` (PR #87848)

[Ben Langmuir via cfe-commits]

https://github.com/benlangmuir approved this pull request.

LGTM (with the `Not to be committed, just here as a demonstration` test removed, of course).

https://github.com/llvm/llvm-project/pull/87848