[fix] actually move tx_check.cpp from libserver to libbitcoin consensus
I messed up https://reviews.bitcoinabc.org/D5961, it is still on libserver
for the cmake build.
ninja check-all [with -DBUILD_BITCOIN_WALLET=OFF as well] make check-recursive ./test/functional/test_runner.py [with --disable-wallet as well]
Reviewers: #bitcoin_abc, jasonbcox
Reviewed By: #bitcoin_abc, jasonbcox
Differential Revision: https://reviews.bitcoinabc.org/D6789