deprecate tickSize in graphql api, generate tickSize string at market submission

[jeremyletang]

This mark TickSize in input parameters as deprecated.
The tickSize is mostly here for informational purpose now, and generated at market submission from the decimalPlace.
It's also a string to avoid any funny behaviour with float precision.

close #1935

[vega-ci-bot]

system-tests failed.

=== Test summary ===
../../grpcTesting/accounts/accountsTests.py F                            [100%]
 testWithdrawAsset 
../../grpcTesting/devnet/sanityTests.py ......F                          [100%]
 testOpenVoteNewMarketProposal 
../../grpcTesting/governance/newMarketGovTests.py EEEEEEEEEEEEEEEEEEEEEx [ 47%]
EEEEEEEEEEEEEEEEEEEEEEEE                                                 [100%]
 ERROR at setup of testVoteNDecline 
 ERROR at setup of testVoteYEnactedFail 
 ERROR at setup of testVoteYNProposalDraw 
 ERROR at setup of testVoteYYNProposalPass 
 ERROR at setup of testNewMarketRejectNoStake 
 ERROR at setup of testNewMarketValidProposal 
 ERROR at setup of testGetAllProposals 
 ERROR at setup of testGetAllOfTheProposals[6] 
 ERROR at setup of testGetNewMarketProposals[6] 
 ERROR at setup of testGetAllOfTheProposals[2] 
 ERROR at setup of testGetNewMarketProposals[2] 
 ERROR at setup of testGetAllOfTheProposals[5] 
 ERROR at setup of testGetNewMarketProposals[5] 
 ERROR at setup of testGetAllOfTheProposals[4] 
 ERROR at setup of testGetNewMarketProposals[4] 
 ERROR at setup of testGetAllOfTheProposals[3] 
 ERROR at setup of testGetNewMarketProposals[3] 
 ERROR at setup of testGetProposalsByParty 
 ERROR at setup of testGetRejectedProposalsByParty 
 ERROR at setup of testGetOpenProposalsByParty 
 ERROR at setup of testGetVotesByParty 
 ERROR at setup of testNewMarketOpenSingleTok 
 ERROR at setup of testVoteYSmallHolder 
 ERROR at setup of testVoteYMediumNSmallHolder 
 ERROR at setup of testVoteTopUpSmallDuringVote 
 ERROR at setup of testVoteYNNoFundsProposal 
 ERROR at setup of testNewMarketInvalidParty 
 ERROR at setup of testInvalidEnactTime 
 ERROR at setup of testVoteYOwnOpenProposal 
 ERROR at setup of testVoteYOpenProposal 
 ERROR at setup of testVoteNOpenProposal 
 ERROR at setup of testVoteNoStakeOpenProposal 
 ERROR at setup of testVoteNoStakeAddFunds 
 ERROR at setup of testVoteRejectProposal 
 ERROR at setup of testVotePassedProposal 
 ERROR at setup of testVoteBothYNOpen 
 ERROR at setup of testVoteTwiceYSameUser 
 ERROR at setup of testVoteInvalidProposalID 
 ERROR at setup of testVoteEnactedMarket 
 ERROR at setup of testVoteDeclinedMarket 
 ERROR at setup of testVoteYTaintedKey 
 ERROR at setup of testNewMarketClosedProposal 
 ERROR at setup of testSubmitEnactedGTCOrder 
 ERROR at setup of testSubmitUnEnactedMarketGTCOrder 
 ERROR at setup of testFiftyYesVoteProposal 
../../grpcTesting/governance/newMarketTradesTests.py EEEEEEEEEEE         [100%]
 ERROR at setup of testTradeGTCToGTC 
 ERROR at setup of testTradeGTTToGTT 
 ERROR at setup of testTradeGTCToIOC 
 ERROR at setup of testTradeGTCToFOK 
 ERROR at setup of testTradesByParty 
 ERROR at setup of testPositionsByParty 
 ERROR at setup of testCloseOutTradeGen 
 ERROR at setup of testTradesByMarket 
 ERROR at setup of testCheckClosedOutTraderPositionsBalance 
 ERROR at setup of testTradeGTTToIOC 
 ERROR at setup of testTradeGTTToFOK 
../../grpcTesting/margins/marginsTests.py .                              [100%]
../../grpcTesting/markets/marketsTests.py ..............                 [100%]
../../grpcTesting/orders/amendOrdersTests.py .......................s... [ 93%]
.x                                                                       [100%]
../../grpcTesting/orders/cancelOrdersTests.py .......................    [100%]
../../grpcTesting/orders/generalOrdersTests.py .x....                    [100%]
../../grpcTesting/orders/limitOrdersTests.py ...........                 [100%]
../../grpcTesting/orders/marketOrdersTests.py ........                   [100%]
../../grpcTesting/orders/mixedOrdersTests.py .....................       [100%]
../../grpcTesting/orders/negativeOrdersTests.py ........................ [ 57%]
....x.........s...                                                       [100%]
../../grpcTesting/parallel/submitParallelOrdersTests.py ........         [100%]
../../grpcTesting/parties/partiesTests.py ..                             [100%]
../../grpcTesting/trading/positionsTests.py ..                           [100%]
../../grpcTesting/trading/tradesTests.py .........F..                    [100%]
 testTradeGTTToIOC 
../../grpcTesting/wallet/walletTests.py ................................ [ 76%]
..........                                                               [100%]
../../rest/orders/negativeOrdersTests.py .                               [100%]

[edd]

The change looks good to me but I will leave it for someone who is reading the code a bit closer