[clang] [clang][ASTImporter] Remove type from ImportedTypes cache on Decl import failure (PR #214008)

[Balázs Kéri via cfe-commits]

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

LGTM if test failures are fixed (the failures look not related to the change, probably branch update fixes the problem).

https://github.com/llvm/llvm-project/pull/214008