`doi-insert-bibtex` results in HTTP 404 error

[tmalsburg]

Recipe:

1. M-x doi-insert-bibtex RET
2. Enter 10.1111/lnc3.12398 RET

Result is:

Fetching https://doi.org/10.1111/Inc3.12398
Contacting host: doi.org:443
Error while processing request: (biblio--url-error http . 404)

Tested with

GNU Emacs 28.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.20, cairo version 1.16.0) of 2020-11-30

Note: Potentially related to #36 and #33?