Move simulate_transaction from rpc to bank

[garious]

Problem

Simulating transactions is unavailable outside solana_core's rpc module.

Summary of Changes

Move that function to the bank.

[codecov]

Codecov Report

Merging #11294 into master will increase coverage by 0.0%.
The diff coverage is 100.0%.

@@           Coverage Diff           @@
##           master   #11294   +/-   ##
=======================================
  Coverage    82.5%    82.5%           
=======================================
  Files         316      316           
  Lines       74539    74543    +4     
=======================================
+ Hits        61500    61517   +17     
+ Misses      13039    13026   -13