In a package.json file, the "typings" or "types" field could be an array
of typings files. ngcc would previously crash unexpectedly for such
packages, as it assumed that the typings field would be a string. This
commit lets ngcc skip over such packages, as having multiple typing
entry-points is not supported for Angular packages so it is safe to
ignore them.
Fixes#33646
PR Close#33973