Incorrect extraction of account number for Iceland, Mauritius, Ireland, Seychelles, Portugal, Montenegro

[julienaltieri]

Describe the bug
Account number is not correct or missing for Iceland, Mauritius, Ireland, Seychelles, Portugal, Montenegro.

To Reproduce
run ibantools.extractIBAN(iban) from node.js (latest npm version)
Iceland
Mauritius
Ireland
Seychelles
Portugal
Montenegro

Note: I haven't checked all the countries but the pattern seems to be that it's incorrect when the country's IBAN format does not end with the account number. (more info on my testing source at the bottom)

Expected behavior
Account numbers should be correct and populated for all these countries.

Environment:
node.js ibantools v4.5.1

Additional context
To replicate easily and fix globally:

• IBAN structure for all countries that implement it: https://en.wikipedia.org/wiki/International_Bank_Account_Number#IBAN_formats_by_country (note that the aforementioned countries end their IBANs with either check digits, currency code, or even national id number of the account holder (Iceland)
• Sample IBANs for each country: https://www.iban.com/structure