algol68g: Add version 3.5.1

[bharatvaj]

• Checked the zip file with virustotal manually

• [x] I have read the Contributing Guide.

[github-actions[bot]]

All changes look good.

Wait for review from human collaborators.

algol68g

• [x] Description
• [x] License
• [x] Hashes
• [x] Checkver
• [x] Autoupdate