fix wrong behavior: submit multisig txn only there are enough signatures

[templexxx]

Pull request type

Please check the type of change your PR introduces:

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

What is the current behavior?

Ignore signatrues' count but submit directly because my mistake.

Issue Number: N/A

What is the new behavior?

• Checking signatures enough or not before submit.
• Adding multisig testing: submit txn by local txn signature file

Other information

[codecov]

Codecov Report

Merging #3482 (7377a35) into master (c656e4b) will decrease coverage by 0.24%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3482      +/-   ##
==========================================
- Coverage   31.29%   31.06%   -0.23%     
==========================================
  Files         500      500              
  Lines       46900    46900              
  Branches    22129    22129              
==========================================
- Hits        14675    14564     -111     
+ Misses      18109    18022      -87     
- Partials    14116    14314     +198     

Flag	Coverage Δ
unittests	31.06% <ø> (-0.23%)	⬇️

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

Impacted Files	Coverage Δ
cmd/starcoin/src/cli_state.rs	48.79% <ø> (-4.87%)	⬇️
rpc/server/src/module/mod.rs	0.00% <0.00%> (-16.66%)	⬇️
...mons/forkable-jellyfish-merkle/src/iterator/mod.rs	41.50% <0.00%> (-10.00%)	⬇️
vm/types/src/on_chain_config/mod.rs	42.47% <0.00%> (-9.58%)	⬇️
chain/open-block/src/lib.rs	31.79% <0.00%> (-9.27%)	⬇️
executor/src/block_executor.rs	24.45% <0.00%> (-8.88%)	⬇️
consensus/src/dummy.rs	65.22% <0.00%> (-8.69%)	⬇️
vm/natives/src/vector.rs	16.67% <0.00%> (-8.33%)	⬇️
vm/types/src/transaction/error.rs	3.58% <0.00%> (-7.14%)	⬇️
chain/src/verifier/mod.rs	35.16% <0.00%> (-7.03%)	⬇️
... and 69 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update c656e4b...7377a35. Read the comment docs.

[templexxx]

Need to fix the submit-txn, I wonder how to get value directlly in test like this?

{
  "ok": "/94713c208ff452d4d02c5446eb18f5ab538b72976e08a84cada4b08be68583ab.multisig-txn"
}

[jolestar]

Need to fix the submit-txn, I wonder how to get value directlly in test like this?

{
  "ok": "/94713c208ff452d4d02c5446eb18f5ab538b72976e08a84cada4b08be68583ab.multisig-txn"
}

use @$ to get the previous command output.

or you can return a struct like:

{
  "ok": {"output_file": "/xxxx"}
}

use @$.output_file to get the response field output_file