Remove all #include // for * comments

Summary:
Most of them have been removed along the backport already.

Partial backport of core#23280:
https://github.com/bitcoin/bitcoin/pull/23280/commits/3b1584b794499158e0df07bd1bee1b803c568614

Depends on D12583.

Test Plan: Read the code.

Reviewers: #bitcoin_abc, PiRK

Reviewed By: #bitcoin_abc, PiRK

Differential Revision: https://reviews.bitcoinabc.org/D12584