net: Remove g_relay_txes
Summary:
g_relay_txes is only required inside net_processing and is set only once at startup. Instead of having a global, move it to be a const member of PeerManager. This requires moving PushNodeVersion() into PeerManager, which also allows us to remove the connman argument.
Backport of core#20217.
Ref T1696.
Test Plan:
ninja all check-all
Reviewers: #bitcoin_abc, PiRK
Reviewed By: #bitcoin_abc, PiRK
Maniphest Tasks: T1696
Differential Revision: https://reviews.bitcoinabc.org/D10884