Validator throws error on multisignature registration

[Tschakki]

Expected behavior

It should be possible to register a multi-signature account without any optional keys.

Actual behavior

Validator throws error, if no optional keys are provided:

Steps to reproduce

$ lisk-core transaction:create auth registerMultisignature 100000000
? Please enter passphrase:  [hidden]
? Please enter: numberOfSignatures:  2
? Please enter: mandatoryKeys(comma separated values (a,b)):
61d320f822fcc163489499200ae6c99a66296513b1ca1066e49a37a026434ac0,dfbe4e3999138d62047c23f61f222a91b24d9d056db055be24f9ab6d95d7aa78
? Please enter: optionalKeys(comma separated values (a,b)):
? Please enter: signatures(comma separated values (a,b)):
85ac61c373218cdf5e0e58a22c9b9ae71cfaf1450062d0302166b60a1cdc3b638eb747ba87c43af20d66b8e9d7513fb1d4cd3800a82debd30f0dc41937cef70e,e17d
67b24c1f0ab207a194bd1a1781b1c8c3110bcb427cd26f84f3034afc567583e021df575881c396e286198f4a36749055e717eaa56cd3f1fd2f3d7835b70d
    Error: Lisk validator found 1 error[s]:
    Property '.optionalKeys.0' minLength not satisfied

Which version(s) does this affect? (Environment, OS, etc...)

Ubuntu 22, beta.1

[bobanm]

Good catch. Just to make the issue description more complete:

It should be possible to register a multi-signature account without any optional keys.

It should be possible to register a multi-signature account without either mandatory or optional keys.