prepare 2.8.0-SNAPSHOT

[liubao68]

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[codecov-commenter]

Codecov Report

Merging #3243 (80e84bf) into master (ffbb73b) will increase coverage by 0.02%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master    #3243      +/-   ##
============================================
+ Coverage     77.48%   77.50%   +0.02%     
  Complexity     1439     1439              
============================================
  Files          1629     1629              
  Lines         43409    43409              
  Branches       3652     3652              
============================================
+ Hits          33634    33644      +10     
+ Misses         8267     8261       -6     
+ Partials       1508     1504       -4     

Impacted Files	Coverage Δ
...mb/config/ConfigCenterConfigurationSourceImpl.java	9.57% <0.00%> (-1.07%)	⬇️
...egistry/client/http/ServiceRegistryClientImpl.java	71.31% <0.00%> (+1.14%)	⬆️
...he/servicecomb/foundation/common/net/NetUtils.java	66.40% <0.00%> (+1.60%)	⬆️
...mb/serviceregistry/client/http/RestClientUtil.java	80.37% <0.00%> (+1.86%)	⬆️
...ecomb/provider/pojo/PojoConsumerMetaRefresher.java	78.04% <0.00%> (+2.43%)	⬆️

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