fix: add metrics basic support

[LaurenceLiZhixin]

• 增加了 Metrics 配置字段
• 增加了默认 Metrics 接口支持
• 默认启动9090端口数据上报
• protocolIDs -> protocol-ids | registryIDs -> registry-ids

后需要做的；

• push gateway 支持
• invocation 的 metrics 默认收集：tps/rt + 必要的label，删除已有意义不大的直方图指标

Fixes #1541

[codecov-commenter]

Codecov Report

Merging #1540 (500342a) into 3.0 (a45fd29) will increase coverage by 0.20%.
The diff coverage is 46.15%.

❗ Current head 500342a differs from pull request most recent head 4d4fb6e. Consider uploading reports for the commit 4d4fb6e to get more accurate results

@@            Coverage Diff             @@
##              3.0    #1540      +/-   ##
==========================================
+ Coverage   41.75%   41.95%   +0.20%     
==========================================
  Files         258      258              
  Lines       15111    15121      +10     
==========================================
+ Hits         6309     6344      +35     
+ Misses       8068     8037      -31     
- Partials      734      740       +6     

Impacted Files	Coverage Δ
config/consumer_config.go	24.74% <ø> (ø)
config/provider_config.go	24.65% <ø> (ø)
config/reference_config.go	0.00% <ø> (ø)
config/router_config.go	5.26% <ø> (ø)
config/service_config.go	9.39% <ø> (ø)
metrics/prometheus/reporter.go	40.55% <34.14%> (-1.02%)	⬇️
config/metric_config.go	66.66% <60.00%> (+45.23%)	⬆️
common/extension/metrics.go	71.42% <100.00%> (ø)
filter/metrics/filter.go	85.00% <100.00%> (-15.00%)	⬇️
... and 9 more

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[LaurenceLiZhixin]

CI may passed after pr: https://github.com/apache/dubbo-go-samples/pull/281/files merged

[justxuewei]

LGTM