chore: record mined block error

[simlecode]

关联的Issues (Related Issues)

改动 (Proposed Changes)

1. 打印出块错误信息
2. 降低计算出块权接口输出日志的级别到 warn

附注 (Additional Info)

自查清单 (Checklist)

在你认为本 PR 满足被审阅的标准之前，需要确保 / Before you mark the PR ready for review, please make sure that:

• 符合Venus项目管理规范中关于PR的相关标准 / The PR follows the PR standards set out in the Venus project management guidelines
• 具有清晰明确的commit message / All commits have a clear commit message.
• 包含相关的的测试用例或者不需要新增测试用例 / This PR has tests for new functionality or change in behaviour or not need to add new tests.
• 包含相关的的指南以及文档或者不需要新增文档 / This PR has updated usage guidelines and documentation or not need
• 通过必要的检查项 / All checks are green

[codecov-commenter]

Codecov Report

Merging #237 (edfa2c5) into master (9ca976c) will decrease coverage by 0.02%.
The diff coverage is 50.00%.

❗ Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #237      +/-   ##
==========================================
- Coverage   47.30%   47.28%   -0.02%     
==========================================
  Files          45       45              
  Lines        3093     3094       +1     
==========================================
  Hits         1463     1463              
- Misses       1455     1456       +1     
  Partials      175      175              

Flag	Coverage Δ
unittests	51.99% <50.00%> (-0.02%)	⬇️

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

Files	Coverage Δ
miner/miningmgr.go	65.70% <100.00%> (ø)
miner/multiminer.go	62.30% <0.00%> (-0.08%)	⬇️