Make native staking contract be loadable from genesis

[zjshen14]

Allow config nativestakingcontractcode in the genesis so that we could start a chain with the native staking contract from scratch.

Verified the start and restart in the cluster and worked fine

[codecov]

Codecov Report

Merging #1542 into master will decrease coverage by 0.23%.
The diff coverage is 16.17%.

@@            Coverage Diff             @@
##           master    #1542      +/-   ##
==========================================
- Coverage   55.27%   55.04%   -0.24%     
==========================================
  Files         149      149              
  Lines       13085    13146      +61     
==========================================
+ Hits         7233     7236       +3     
- Misses       4922     4976      +54     
- Partials      930      934       +4

Impacted Files	Coverage Δ
server/itx/server.go	22.79% <ø> (ø)	⬆️
blockchain/genesis/genesis.go	65.57% <ø> (ø)	⬆️
action/protocol/execution/evm/evm.go	31.9% <0%> (ø)	⬆️
action/protocol/poll/staking_committee.go	0% <0%> (ø)	⬆️
action/protocol/poll/protocol.go	42.85% <0%> (-0.64%)	⬇️
blockchain/blockchain.go	45.08% <4.34%> (-2.38%)	⬇️
action/protocol/poll/nativestaking.go	32.97% <81.81%> (+0.79%)	⬆️
db/trie/branchnode.go	65.59% <0%> (-1.61%)	⬇️

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