[linter] fix check-doc

Summary: I somehow did a rebase mistake before landing D11947, so this change was not included. This breaks the check-doc linter, which fails to recognize GetIntArg as a valid use of a documented parameter.

Test Plan: arc lint

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D11951