1.5 fix the nacos namespace from server/client.yml does not take e…

[Mulavar]

…ffect

What this PR does:

Which issue(s) this PR fixes:

Fixes # #1573

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

[codecov-commenter]

Codecov Report

Merging #1576 (e785d0d) into 1.5 (a4b4f50) will increase coverage by 0.02%.
The diff coverage is 54.16%.

❗ Current head e785d0d differs from pull request most recent head 2cb57ab. Consider uploading reports for the commit 2cb57ab to get more accurate results

@@            Coverage Diff             @@
##              1.5    #1576      +/-   ##
==========================================
+ Coverage   55.72%   55.75%   +0.02%     
==========================================
  Files         279      279              
  Lines       16024    16072      +48     
==========================================
+ Hits         8930     8961      +31     
- Misses       6153     6167      +14     
- Partials      941      944       +3     

Impacted Files	Coverage Δ
common/logger/logger.go	92.75% <ø> (ø)
common/logger/logging.go	80.00% <0.00%> (-20.00%)	⬇️
config/config_center_config.go	66.21% <ø> (+5.19%)	⬆️
config/consumer_config.go	58.69% <ø> (ø)
config/protocol_config.go	100.00% <ø> (ø)
protocol/dubbo/impl/package.go	62.06% <ø> (ø)
protocol/invocation/rpcinvocation.go	16.66% <0.00%> (-0.61%)	⬇️
registry/service_instance.go	0.00% <ø> (ø)
protocol/dubbo/impl/codec.go	41.50% <20.00%> (-0.16%)	⬇️
registry/nacos/registry.go	43.84% <40.00%> (-0.51%)	⬇️
... and 12 more

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[Mulavar]

不删除原有常量是发现有其他地方在用（apollo、file），尚不清楚这两个的具体实现，因此为了避免歧义新增了常量。