The recently introduced typings-only mode in ngcc would incorrectly
write compiled JavaScript files if typings-only mode was requested, in
case the typings of the entry-point had already been processed in a
prior run of ngcc. The corresponding format property for which the
JavaScript files were written were not marked as processed, though, as
the typings-only mode excluded the format property itself from being
marked as processed. Consequently, subsequent runs of ngcc would not
consider the entry-point to have been processed and recompile the
JavaScript bundle once more, resulting in duplicate ngcc imports.
Fixes#41198
PR Close#41209