rpc&&miner: Update miner && related apis

[sanlee42]

APIs change:

1. Return block hash in minting.submit
2. Add prevous_hash in subscribe MintBlockEvent
3. Add new rpc mining.get_job for getting MintBlockEvent

Optimize codes:

1. Clean struct MintBlock
2. Send seal event to MinerService instead of bus

[codecov]

Codecov Report

Merging #2534 (9af92be) into master (614ea16) will increase coverage by 0.24%.
The diff coverage is 17.08%.

@@            Coverage Diff             @@
##           master    #2534      +/-   ##
==========================================
+ Coverage   32.93%   33.17%   +0.24%     
==========================================
  Files         498      498              
  Lines       43219    43287      +68     
  Branches    19574    19593      +19     
==========================================
+ Hits        14230    14356     +126     
+ Misses      14383    14224     -159     
- Partials    14606    14707     +101     

Flag	Coverage Δ
unittests	33.17% <17.08%> (+0.24%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
cmd/miner_client/src/job_client.rs	0.00% <0.00%> (ø)
node/src/node.rs	12.99% <0.00%> (ø)
rpc/api/src/miner.rs	0.00% <0.00%> (ø)
rpc/api/src/types.rs	16.55% <0.00%> (+0.98%)	⬆️
rpc/api/src/types/pubsub.rs	29.79% <0.00%> (ø)
rpc/client/src/lib.rs	14.59% <0.00%> (+0.47%)	⬆️
rpc/client/src/pubsub_client.rs	24.33% <0.00%> (ø)
rpc/server/src/module/miner_rpc.rs	9.68% <0.00%> (-5.32%)	⬇️
stratum/src/rpc.rs	2.44% <0.00%> (ø)
stratum/src/stratum.rs	17.65% <0.00%> (+0.34%)	⬆️
... and 48 more

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[github-actions]

Benchmark for 6d49546

Click to view benchmark

Test	PR Benchmark	Master Benchmark	%
accumulator_append	2.7±0.80ms	2.5±0.11ms	+8.00%
block_apply/block_apply_10	483.3±6.72ms	479.2±15.08ms	+0.86%
block_apply/block_apply_1000	49.2±1.06s	48.3±0.90s	+1.86%
get_with_proof/db_store	38.3±0.24µs	38.2±0.38µs	+0.26%
get_with_proof/mem_store	31.7±0.22µs	31.5±0.25µs	+0.63%
put_and_commit/db_store/1	1506.4±55.39µs	1760.1±194.97µs	-14.41%
put_and_commit/db_store/10	2.7±0.44ms	2.8±0.57ms	-3.57%
put_and_commit/db_store/100	9.8±1.24ms	9.9±1.34ms	-1.01%
put_and_commit/db_store/5	2.1±0.20ms	2.2±0.21ms	-4.55%
put_and_commit/db_store/50	6.1±0.89ms	6.0±0.85ms	+1.67%
put_and_commit/mem_store/1	63.9±5.78µs	63.1±5.56µs	+1.27%
put_and_commit/mem_store/10	589.6±48.22µs	584.7±45.63µs	+0.84%
put_and_commit/mem_store/100	5.7±0.81ms	5.7±0.80ms	0.00%
put_and_commit/mem_store/5	298.3±25.07µs	297.4±23.82µs	+0.30%
put_and_commit/mem_store/50	2.9±0.18ms	2.9±0.18ms	0.00%
query_block/query_block_in(10)_times(100)	2.9±0.11ms	2.9±0.06ms	0.00%
query_block/query_block_in(10)_times(1000)	29.3±0.84ms	29.2±0.24ms	+0.34%
query_block/query_block_in(10)_times(10000)	297.2±7.41ms	289.2±6.03ms	+2.77%
query_block/query_block_in(1000)_times(100)	929.8±14.39µs	908.5±2.02µs	+2.34%
query_block/query_block_in(1000)_times(1000)	9.2±0.05ms	9.1±0.05ms	+1.10%
query_block/query_block_in(1000)_times(10000)	93.0±0.42ms	91.3±0.39ms	+1.86%
storage_transaction	64.8±4.26ms	60.2±5.14ms	+7.64%
vm/transaction_execution/1	332.3±0.86ms	332.4±2.07ms	-0.03%
vm/transaction_execution/10	111.6±0.55ms	113.1±5.93ms	-1.33%
vm/transaction_execution/20	105.0±0.37ms	105.4±1.27ms	-0.38%
vm/transaction_execution/5	133.5±0.54ms	134.2±2.23ms	-0.52%
vm/transaction_execution/50	120.8±0.76ms	122.0±5.01ms	-0.98%