converters/bibtexconv: Update 2.1.1 => 2.2.0

Changelog:
https://github.com/dreibh/bibtexconv/blob/bibtexconv-2.2.0/ChangeLog

Commit log:
https://github.com/dreibh/bibtexconv/compare/bibtexconv-2.1.1...bibtexconv-2.2.0

PR: 294635
Sponsored by: UNIS Labs