It meets Cpp17RandomAccessIterator requirements, but does not satisfy
random_access_iterator concept.
libstdc++-v3/ChangeLog:
* testsuite/util/testsuite_iterators.h: Modify comment.
Reviewed-by: Jonathan Wakely <jwakely@redhat.com>
Signed-off-by: Tomasz Kamiński <tkaminsk@redhat.com>