Changes to make MaybeSendAddr simpler and easier to maintain/update:
- assert invariant that node.vAddrToSend.size() can never exceed
MAX_ADDR_TO_SEND
- erase known addresses from vAddrToSend in one pass
- no check for (vAddr.size() >= MAX_ADDR_TO_SEND) during iteration,
since vAddr can never exceed MAX_ADDR_TO_SEND.
Note: we used `GetMaxAddrToSend()` instead of `MAX_ADDR_TO_SEND` because it can be overriden by the `-maxaddrtosend` command line option (D10823]
This concludes backport of core#21236 [6/6]
https://github.com/bitcoin/bitcoin/pull/21236/commits/935d4889228e7e361c8b0020761fa0e08a55fb48
Depends on D10919