value property
A value is the optional value of the tag. The string value can be 1-256
Unicode characters in length and can't be prefixed with "aws:" or "dms:".
The string can only contain only the set of Unicode letters, digits,
white-space, '_', '.', '/', '=', '+', '-' (Java regular expressions:
"^(\p{L}\p{Z}\p{N}_.:/=+\-*)$").
Implementation
final String? value;