use hyphen instead of camel for prefix

[beiwei30]

What is the purpose of the change

we should use hyphen case instead of camel case in dubbo.properties, for example:

dubbo.config-center.Foo instead of dubbo.configCenter.Foo

Brief changelog

XXXXX

Verifying this change

XXXXX

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[codecov-io]

Codecov Report

Merging #3119 into master will decrease coverage by 0.14%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master    #3119      +/-   ##
============================================
- Coverage     63.67%   63.52%   -0.15%     
  Complexity       75       75              
============================================
  Files           652      652              
  Lines         28190    28190              
  Branches       4784     4784              
============================================
- Hits          17950    17908      -42     
- Misses         7989     8026      +37     
- Partials       2251     2256       +5

Impacted Files	Coverage Δ	Complexity Δ
...g/context/annotation/DubboConfigConfiguration.java	66.66% <ø> (ø)	0 <0> (ø)	⬇️
.../apache/dubbo/qos/protocol/QosProtocolWrapper.java	64.1% <0%> (-17.95%)	0% <0%> (ø)
.../remoting/transport/netty4/NettyServerHandler.java	73.52% <0%> (-11.77%)	0% <0%> (ø)
.../remoting/transport/netty4/NettyClientHandler.java	75% <0%> (-11.12%)	0% <0%> (ø)
...in/java/org/apache/dubbo/common/utils/JVMUtil.java	73.58% <0%> (-7.55%)	0% <0%> (ø)
...ava/org/apache/dubbo/config/DubboShutdownHook.java	78.12% <0%> (-6.25%)	0% <0%> (ø)
...ng/transport/dispatcher/all/AllChannelHandler.java	51.42% <0%> (-5.72%)	0% <0%> (ø)
.../org/apache/dubbo/remoting/ExecutionException.java	15.78% <0%> (-5.27%)	0% <0%> (ø)
...e/dubbo/remoting/transport/netty/NettyChannel.java	57.64% <0%> (-4.71%)	0% <0%> (ø)
.../apache/dubbo/remoting/transport/AbstractPeer.java	63.04% <0%> (-4.35%)	0% <0%> (ø)
... and 10 more

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[khanimteyaz]

Looks fine to me.

[ralf0131]

LGTM.