[doc] Add code lines statistics to readme

[jolestar]

Pull request type

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• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Other information

[codecov]

Codecov Report

Merging #3265 (154a85f) into master (86d4dcd) will increase coverage by 0.29%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3265      +/-   ##
==========================================
+ Coverage   31.88%   32.16%   +0.29%     
==========================================
  Files         499      499              
  Lines       46240    46240              
  Branches    21215    21215              
==========================================
+ Hits        14737    14869     +132     
+ Misses      17550    17421     -129     
+ Partials    13953    13950       -3     

Flag	Coverage Δ
unittests	32.16% <ø> (+0.29%)	⬆️

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

Impacted Files	Coverage Δ
rpc/server/src/module/mod.rs	0.00% <0.00%> (-16.66%)	⬇️
vm/types/src/transaction/error.rs	3.58% <0.00%> (-10.71%)	⬇️
state/state-store-api/src/lib.rs	43.75% <0.00%> (-6.25%)	⬇️
network-rpc/core/src/lib.rs	24.00% <0.00%> (-6.00%)	⬇️
cmd/starcoin/src/cli_state.rs	48.79% <0.00%> (-4.87%)	⬇️
chain/src/verifier/mod.rs	41.33% <0.00%> (-4.13%)	⬇️
vm/transaction-builder/src/lib.rs	23.97% <0.00%> (-3.42%)	⬇️
network-rpc/api/src/lib.rs	18.10% <0.00%> (-2.85%)	⬇️
storage/src/transaction_info/mod.rs	46.52% <0.00%> (-2.32%)	⬇️
commons/accumulator/src/inmemory/mod.rs	69.70% <0.00%> (-2.27%)	⬇️
... and 110 more

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[github-actions]

Benchmark for cf22e2d

Click to view benchmark

Test	Base	PR	%
accumulator_append	590.7±12.69µs	588.8±10.57µs	-0.32%
block_apply/block_apply_10	267.4±1.08ms	268.1±1.02ms	+0.26%
block_apply/block_apply_1000	27.4±0.05s	27.3±0.02s	-0.36%
get_with_proof/db_store	36.4±0.52µs	35.8±0.44µs	-1.65%
get_with_proof/mem_store	31.3±0.24µs	31.0±0.31µs	-0.96%
put_and_commit/db_store/1	95.5±4.81µs	93.7±4.92µs	-1.88%
put_and_commit/db_store/10	852.0±44.04µs	848.1±40.06µs	-0.46%
put_and_commit/db_store/100	7.3±0.31ms	7.3±0.33ms	0.00%
put_and_commit/db_store/5	434.9±21.59µs	432.0±21.23µs	-0.67%
put_and_commit/db_store/50	3.8±0.17ms	3.8±0.18ms	0.00%
put_and_commit/mem_store/1	61.3±5.64µs	61.0±5.33µs	-0.49%
put_and_commit/mem_store/10	574.9±48.56µs	572.6±45.13µs	-0.40%
put_and_commit/mem_store/100	5.6±0.84ms	5.6±0.79ms	0.00%
put_and_commit/mem_store/5	291.1±25.54µs	286.9±23.57µs	-1.44%
put_and_commit/mem_store/50	2.8±0.18ms	2.8±0.18ms	0.00%
query_block/query_block_in(10)_times(100)	3.9±0.14ms	3.9±0.18ms	0.00%
query_block/query_block_in(10)_times(1000)	38.9±0.82ms	39.1±0.63ms	+0.51%
query_block/query_block_in(10)_times(10000)	388.1±9.64ms	386.3±7.58ms	-0.46%
query_block/query_block_in(1000)_times(100)	933.5±5.64µs	945.1±11.33µs	+1.24%
query_block/query_block_in(1000)_times(1000)	9.3±0.09ms	9.5±0.11ms	+2.15%
query_block/query_block_in(1000)_times(10000)	93.5±0.87ms	94.4±1.13ms	+0.96%
storage_transaction	1047.0±295.98µs	1051.8±317.20µs	+0.46%
vm/transaction_execution/1	316.9±1.59ms	317.6±2.16ms	+0.22%
vm/transaction_execution/10	99.1±0.39ms	98.8±0.41ms	-0.30%
vm/transaction_execution/20	91.2±0.22ms	91.2±0.53ms	0.00%
vm/transaction_execution/5	121.6±0.65ms	121.8±1.25ms	+0.16%
vm/transaction_execution/50	103.5±0.57ms	103.2±1.27ms	-0.29%