Add test for invalid check digits.
Add test for invalid check digits.

The final stage of the checksum calculation is to subtract the remainder
of a division by 97 (0-96) from 98.  Valid values are thus 02 to 98.  An
LEI which ends in 00,01 or 99 is thus not valid even if the remainder of
dividing by 97 is 1.

otisid/lei-js-validator