add UTXOs counting to GetBalanceByAddress request

[Aleoami]

So to see who's bought and who's mined coins, and maybe incentivize people to compound their balances seeing the huge number of funds' chunks

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 16 lines in your changes missing coverage. Please review.

Project coverage is 59.25%. Comparing base (3908f27) to head (5f5d91a).
Report is 83 commits behind head on dev.

Files with missing lines	Patch %	Lines
app/rpc/rpchandlers/get_balance_by_address.go	0.00%	7 Missing ⚠️
app/appmessage/rpc_get_balance_by_address.go	0.00%	3 Missing ⚠️
app/rpc/rpchandlers/get_balances_by_addresses.go	0.00%	2 Missing ⚠️
...grpcserver/protowire/rpc_get_balance_by_address.go	0.00%	2 Missing ⚠️
...cserver/protowire/rpc_get_balances_by_addresses.go	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              dev    #2080      +/-   ##
==========================================
- Coverage   59.32%   59.25%   -0.08%     
==========================================
  Files         678      678              
  Lines       32594    32600       +6     
==========================================
- Hits        19337    19316      -21     
- Misses      10467    10489      +22     
- Partials     2790     2795       +5     

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