Audit core limits that depend on network op limits

[marta-lokhova]

Looks like a few places in core don't take into account Soroban limits. Examples are:

• Pull mode

  stellar-core/src/overlay/TxAdverts.cpp

  Line 111 in 86a346a

  while (size() > mApp.getLedgerManager().getLastMaxTxSetSizeOps())

• outbound queues

  stellar-core/src/overlay/FlowControl.cpp

  Line 406 in 86a346a

  uint32_t const limit =

Currently, this isn't much of a problem since Soroban limits are still very low. But we should fix this to support higher limits.