Update question marks of Validation Rules section

Update question marks of Validation Rules section:

• Mendatory: Title: “Mendatory”
  Text: Field value can’t be null. If you want to customize the value displayed on validation error, use Use the following translation key: label.schema.constraint.violation.PatternConstraint.invoice.CustomerName
• Text Format: Title: “Text Format” You can apply a regular expression to validate the structure of the string value. If you want to customize the value displayed on validation error
  Use the following translation key: label.schema.constraint.violation.PatternConstraint.invoice.CustomerName

• Text Length: Title “Text Length”. You can define the accepted range of number of characters for the string value. Range values are inclusive.

(there must be some others in other kinds of fields that should be updated with the same logic)