Remove Reference Links
Summary:
The links are no longer good, and Core decided to remove them rather than update them.
-BEGIN VERIFY SCRIPT-
sed -i '/https:\/\/bitcoin.org\/en\/developer-reference/d' ./src/protocol.h
-END VERIFY SCRIPT-
This is a backport of core#19639
Test Plan: self-review (low risk of accidental change, as there was no conflict and no linter action)
Reviewers: #bitcoin_abc, majcosta
Reviewed By: #bitcoin_abc, majcosta
Differential Revision: https://reviews.bitcoinabc.org/D10052