reconsider statementId length constraints

[kathryn-ods]

Just noting that the statementId requirement of being 32-64 characters has been a bit challenging for Rachel and I when working with PSC/GLEIF mappings to BODS 0.4

• @kd-ods suggested having a prefix "XI-LEI-506700GE1G29325QX363" as a UUID for GLEIF statementIds but that is 27 characters and made them too long.
• @odscrachel has had some issues meeting the minimum length for statementIds when working with PSC data

I think the constraints make sense in that we want to make sure statementIds are sufficiently unique/not unwieldly. However there's a risk of frustration when trying to construct statementIds that are made up of useful information e.g. prefix + registration number + date. It's not ideal to remove useful info/add filler in these cases.