2.x migrate round model

[koenvsteenb]

Migrate RoundModel to be based of zalt-model insteadof MUtil.

Also included with this pull request:

• Fixes Track and Round deletion so that a track can be deleted when it is not used
• Adds laminas/laminas-i18n in order to be able to properly validate (and format) integers. This is not possible with the laminas validator Digits see also
• Reverts the fix for #434 since it does not seem to be an issue anymore
• gro_valid_after_length and gro_valid_for_length are now required to reflect the table scheme
• Fixed Track and Round deletion so that no error will be thrown when deleting a Track or Round which has other tables referencing (with foreign key) said Track or Round

[koenvsteenb]

I added the phpstan errors from the TrackEngineAbstract to the baseline since the function is part of a Track-copy function which is not implemented/accessable for a user.