Merge branch 'hotfix/#6927-#6278-jcb-credit-card-validator-allowed-ranges-update'

Close #6927
Close #6278
Fixed #6941
#6941 #6943 - better handling of skipped MX-related EmailAddress validator network-based tests
Merge branch 'hotfix/#6941-#6943-undefined-constant-check-in-test-suite' into develop

Close #6941
Close #6943
Forward port #6941
Forward port #6943