This unblocks https://github.com/llvm/llvm-project/pull/158606. The tests are failing because libc++ is now using lambdas in function bodies in the vector header. Ever since https://github.com/llvm/llvm-project/issues/149477 we bail out of importing types when we encounter lambdas. Until we fix ASTImport of `clang::LambdaExpr` nodes properly, this will need to be skipped.