script for integration of PEPPOL-EN16931-xxxx rules and test files

• add script for automated integration of peppol rules
  • copy R008 to CII
  • add R044 to CII (nice-to-have)
  • add R046 to CII
  • replace omit R120 in CII (see https://projekte.kosit.org/xrechnung/xrechnung-intern/-/issues/1580#note_1655119
  • flag CII rules as "warning"
  • adapt assert messages in CII rules where necessary (see below)
• add tests for each rule in UBL (Invoice and CreditNote) and CII