Feat/tanlang/improve docker usage

[LinZexiao]

关联的Issues (Related Issues)

invole #5240

改动 (Proposed Changes)

• rm useless dockerfile
• unset InsecurePoStValidation when use 2k
• set docker workdir into PATH
• devide mod download and build
• add default tag to image

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 #5241 (1bdb0b5) into master (e3c427e) will increase coverage by 0%.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #5241   +/-   ##
======================================
  Coverage      24%     24%           
======================================
  Files         590     590           
  Lines       65531   65526    -5     
======================================
+ Hits        16355   16366   +11     
+ Misses      47035   47022   -13     
+ Partials     2141    2138    -3