修复分片上传 v2 的 bug

[bachue]

No description provided.

[codecov]

Codecov Report

Merging #362 (fe63159) into master (1c6bc89) will increase coverage by 1.08%.
The diff coverage is 91.89%.

@@            Coverage Diff             @@
##           master     #362      +/-   ##
==========================================
+ Coverage   86.79%   87.87%   +1.08%     
==========================================
  Files          20       20              
  Lines        1446     1476      +30     
==========================================
+ Hits         1255     1297      +42     
+ Misses        191      179      -12     

Impacted Files	Coverage Δ
src/Qiniu/Http/Client.php	100.00% <ø> (ø)
src/Qiniu/Storage/UploadManager.php	96.55% <ø> (+12.06%)	⬆️
tests/bootstrap.php	92.85% <87.50%> (-7.15%)	⬇️
src/Qiniu/Storage/ResumeUploader.php	77.33% <92.00%> (+3.06%)	⬆️
src/Qiniu/Http/Response.php	76.36% <100.00%> (+1.85%)	⬆️
src/Qiniu/Storage/FormUploader.php	78.57% <0.00%> (+9.52%)	⬆️

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[lihsai0]

测试用例 random 的原因？

GET URL 的时候，这些 URL 后面是有 CDN 的，如果先前上传了一个 key 的文件并且获取过，接下来对这个 key 的文件进行覆盖上传，再获取的时候，CDN 会返回先前缓存的文件内容，造成测试用例失败。