Make de-vs compliance checks more rigid

Change using code of deprecated Kleo::gpgComplianceP() and
Kleo::Formatting::complianceMode() to use the new helpers
Kleo::gnupgUsesDeVsCompliance() or Kleo::gnupgIsDeVsCompliant().

The general rule is: If GnuPG doesn't pass the basic de-vs compliance
check, then it makes no sense to label anything as de-vs compliant.

• GnuPG-bug-id: T5362