[SCB-2805]change default settings for http keepalive timeout and idle…

[liubao68]

… timeout

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[codecov-commenter]

Codecov Report

Merging #3927 (c77bc13) into 2.8.x (7099475) will increase coverage by 0.01%.
The diff coverage is 100.00%.

❗ Current head c77bc13 differs from pull request most recent head c7635c4. Consider uploading reports for the commit c7635c4 to get more accurate results

@@             Coverage Diff              @@
##              2.8.x    #3927      +/-   ##
============================================
+ Coverage     74.43%   74.45%   +0.01%     
  Complexity      690      690              
============================================
  Files          1592     1592              
  Lines         39985    39983       -2     
  Branches       3648     3644       -4     
============================================
+ Hits          29764    29768       +4     
+ Misses         8734     8729       -5     
+ Partials       1487     1486       -1     

Files Changed	Coverage Δ
...dation/vertx/client/http/HttpClientOptionsSPI.java	72.41% <100.00%> (+2.04%)	⬆️
...b/transport/rest/client/TransportClientConfig.java	100.00% <100.00%> (+13.33%)	⬆️
...ecomb/transport/rest/vertx/RestServerVerticle.java	61.84% <100.00%> (+1.29%)	⬆️
...vicecomb/transport/rest/vertx/TransportConfig.java	100.00% <100.00%> (ø)

... and 5 files with indirect coverage changes

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