[SCB-2288]add a configuration for ssl client auth type

[liubao68]

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[codecov-commenter]

Codecov Report

Merging #2469 (adf17da) into master (80dd6d0) will decrease coverage by 0.06%.
The diff coverage is 55.38%.

@@             Coverage Diff              @@
##             master    #2469      +/-   ##
============================================
- Coverage     79.95%   79.89%   -0.07%     
  Complexity     1415     1415              
============================================
  Files          1549     1550       +1     
  Lines         41401    41445      +44     
  Branches       3453     3456       +3     
============================================
+ Hits          33104    33114      +10     
- Misses         6816     6844      +28     
- Partials       1481     1487       +6     

Impacted Files	Coverage Δ
.../org/apache/servicecomb/config/TransportUtils.java	5.08% <0.00%> (-0.28%)	⬇️
.../apache/servicecomb/config/kie/TransportUtils.java	0.00% <0.00%> (ø)
.../apache/servicecomb/foundation/ssl/ClientAuth.java	0.00% <0.00%> (ø)
...omb/serviceregistry/auth/RBACBootStrapService.java	4.87% <0.00%> (-0.19%)	⬇️
.../servicecomb/foundation/vertx/VertxTLSBuilder.java	65.47% <45.45%> (-2.95%)	⬇️
.../apache/servicecomb/foundation/ssl/SSLManager.java	86.77% <67.64%> (-8.37%)	⬇️
...g/apache/servicecomb/foundation/ssl/SSLOption.java	91.07% <80.00%> (+0.34%)	⬆️
...mb/serviceregistry/client/http/RestClientUtil.java	75.70% <0.00%> (-1.87%)	⬇️
...egistry/client/http/ServiceRegistryClientImpl.java	68.85% <0.00%> (-1.17%)	⬇️

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