net: Assume that SetCommonVersion is called at most once per peer
Summary:
This restores the check removed in #17785 (comment)
Instead of using error, which was used previously, it uses a newly
introduced Assume(). error had several issues:
It logs unconditionally to the debug log
It doesn't abort the program when the error is hit in testsBackport of core#20138.
Depends on D9680.
Ref T1611.
Test Plan:
ninja all check-all ninja bitcoin-fuzzers ./src/test/fuzz/net <path_to_corpus>
Reviewers: #bitcoin_abc, PiRK
Reviewed By: #bitcoin_abc, PiRK
Maniphest Tasks: T1611
Differential Revision: https://reviews.bitcoinabc.org/D9682