test: Remove unused call to generate in rpc_mempool_info
test: Remove unused call to generate in rpc_mempool_info

There are already enough blocks

tecnovert/particl-core,tecnovert/particl-core,lateminer/bitcoin,namecoin/namecore,namecoin/namecoin-core,jamesob/bitcoin,ajtowns/bitcoin,lateminer/bitcoin,fanquake/bitcoin,mruddy/bitcoin,bitcoinsSG/bitcoin,bitcoin/bitcoin,bitcoinsSG/bitcoin,bitcoinsSG/bitcoin,jambolo/bitcoin,sipsorcery/bitcoin,Xekyo/bitcoin,mruddy/bitcoin,tecnovert/particl-core,fanquake/bitcoin,Xekyo/bitcoin,fujicoin/fujicoin,Xekyo/bitcoin,AkioNak/bitcoin,particl/particl-core,tecnovert/particl-core,namecoin/namecore,mruddy/bitcoin,bitcoin/bitcoin,namecoin/namecoin-core,sipsorcery/bitcoin,fujicoin/fujicoin,bitcoinsSG/bitcoin,namecoin/namecore,ajtowns/bitcoin,bitcoin/bitcoin,jamesob/bitcoin,namecoin/namecoin-core,jamesob/bitcoin,domob1812/bitcoin,Xekyo/bitcoin,ajtowns/bitcoin,sstone/bitcoin,namecoin/namecoin-core,sstone/bitcoin,sipsorcery/bitcoin,namecoin/namecore,fujicoin/fujicoin,sstone/bitcoin,AkioNak/bitcoin,lateminer/bitcoin,tecnovert/particl-core,namecoin/namecore,Xekyo/bitcoin,particl/particl-core,instagibbs/bitcoin,namecoin/namecoin-core,Xekyo/bitcoin,ajtowns/bitcoin,instagibbs/bitcoin,particl/particl-core,kallewoof/bitcoin,ajtowns/bitcoin,jambolo/bitcoin,instagibbs/bitcoin,jambolo/bitcoin,sstone/bitcoin,sipsorcery/bitcoin,sipsorcery/bitcoin,domob1812/bitcoin,particl/particl-core,lateminer/bitcoin,AkioNak/bitcoin,instagibbs/bitcoin,mruddy/bitcoin,lateminer/bitcoin,lateminer/bitcoin,jambolo/bitcoin,particl/particl-core,jambolo/bitcoin,bitcoinsSG/bitcoin,instagibbs/bitcoin,namecoin/namecoin-core,fujicoin/fujicoin,mruddy/bitcoin,particl/particl-core,namecoin/namecore,bitcoin/bitcoin,fanquake/bitcoin,fanquake/bitcoin,kallewoof/bitcoin,kallewoof/bitcoin,jamesob/bitcoin,fujicoin/fujicoin,bitcoin/bitcoin,AkioNak/bitcoin,jambolo/bitcoin,domob1812/bitcoin,sipsorcery/bitcoin,fanquake/bitcoin,jamesob/bitcoin,bitcoin/bitcoin,jamesob/bitcoin,domob1812/bitcoin,sstone/bitcoin,domob1812/bitcoin,fujicoin/fujicoin,kallewoof/bitcoin,AkioNak/bitcoin,ajtowns/bitcoin,sstone/bitcoin,bitcoinsSG/bitcoin,tecnovert/particl-core,fanquake/bitcoin,domob1812/bitcoin,instagibbs/bitcoin,AkioNak/bitcoin,kallewoof/bitcoin,mruddy/bitcoin,kallewoof/bitcoin