[backport#19304] test: Check that message sends successfully when header is split across two buffers

Summary:
80d4423f997e15780bfa3f91bf4b4bf656b8ea45 Test buffered valid message (Troy Giorshev)

Pull request description:

This PR is a tweak of #19302.  This sends a valid message.

Additionally, this test includes logging in the same vein as #19272.

Depends on D9513

Backport of core#19304

Test Plan:

ninja all && ./test/functional/test_runner.py p2p_invalid_messages

Reviewers: #bitcoin_abc, PiRK

Reviewed By: #bitcoin_abc, PiRK

Differential Revision: https://reviews.bitcoinabc.org/D9514