feat: add simple sample

[tplooker]

Adds a simple sample on how to use the API

Description

• Tests for the changes have been added (for bug fixes / features)
• The commit message(s) follow conventional commits
• Documentation has been added / updated (for bug fixes / features)
• Changes follow the contributing document.

Motivation and Context

Knowledge sharing :)

Does this PR introduce a breaking change?

• Yes
• No

Which merge strategy will you use?

• Squash
• Rebase (REVIEW COMMITS)

[github-actions]

Total Coverage: 84.82%

Coverage Report

File	Branches	Funcs	Lines	Uncovered Lines
src
BbsBlsSignature2020.ts	56.25%	100%	85.56%	109, 114, 119, 123, 205, 206, 304, 305, 308, 309, 327, 328, 332, 333, 347, 348, 368, 369, 370, 45, 46, 49, 56, 57, 61, 64, 68, 69, 70, 70, 70, 71, 92, 94
BbsBlsSignatureProof2020.ts	60%	78.57%	83.72%	139, 140, 148, 250, 251, 256, 294, 296, 300, 306, 337, 342, 354, 355, 357, 358, 376, 377, 381, 382, 58, 59
Bls12381G2KeyPair.ts	68.75%	80%	85.71%	138, 151, 152, 34, 35, 37, 79, 80, 82
deriveProof.ts	50%	100%	80%	31, 32, 38, 39
index.ts	100%	100%	100%
w3cDate.ts	75%	100%	83.33%	20, 21

[github-actions]

Total Coverage: 84.82%

Coverage Report

File	Branches	Funcs	Lines	Uncovered Lines
src
BbsBlsSignature2020.ts	56.25%	100%	85.56%	109, 114, 119, 123, 205, 206, 304, 305, 308, 309, 327, 328, 332, 333, 347, 348, 368, 369, 370, 45, 46, 49, 56, 57, 61, 64, 68, 69, 70, 70, 70, 71, 92, 94
BbsBlsSignatureProof2020.ts	60%	78.57%	83.72%	139, 140, 148, 250, 251, 256, 294, 296, 300, 306, 337, 342, 354, 355, 357, 358, 376, 377, 381, 382, 58, 59
Bls12381G2KeyPair.ts	68.75%	80%	85.71%	138, 151, 152, 34, 35, 37, 79, 80, 82
deriveProof.ts	50%	100%	80%	31, 32, 38, 39
index.ts	100%	100%	100%
w3cDate.ts	75%	100%	83.33%	20, 21