Default URLs for non-4-digit RFCs should not zero fill the RFC number to 4-digits

[kesara]

Describe the issue

Currently, non-4-digit RFCs get zeros to make the RFC number 4 digits ¹.
The UI should show the non-4-digit URL instead of 4-digit URL.
Non-4-digit reference URLs work fine ².

Code of Conduct

• I agree to follow the IETF's Code of Conduct

Footnotes

1. https://bib.ietf.org/get-bibliographic-item/?query=RFC+333 ↩

2. https://bib.ietf.org/public/rfc/bibxml/reference.RFC.333.xml ↩