[New Feature]: Regular expressoins as Constant expressions

[gimantha]

Description

Please refer to the comment: https://github.com/ballerina-platform/ballerina-spec/issues/1132#issuecomment-1203499130

Describe your problem(s)

No response

Describe your solution(s)

No response

Related area

-> Compilation

Related issue(s) (optional)

https://github.com/ballerina-platform/ballerina-spec/issues/1132

Suggested label(s) (optional)

No response

Suggested assignee(s) (optional)

No response