cluster: add ngm metrics to promtheus config

[nexustar]

What problem does this PR solve?

• close prometheus doesn't monitoring the ng-monitoring component #1799
• fix promtheus not connect to node-exporter which node that only has promtheus #1809

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Code changes

• Has exported function/method change
• Has exported variable/fields change
• Has interface methods change
• Has persistent data change

Side effects

• Possible performance regression
• Increased code complexity
• Breaking backward compatibility

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation

Release notes:

NONE

[ti-chi-bot]

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[codecov-commenter]

Codecov Report

Merging #1806 (0c7e437) into master (9798f51) will decrease coverage by 6.04%.
The diff coverage is 17.65%.

@@            Coverage Diff             @@
##           master    #1806      +/-   ##
==========================================
- Coverage   53.07%   47.02%   -6.04%     
==========================================
  Files         303      287      -16     
  Lines       34644    33776     -868     
==========================================
- Hits        18385    15883    -2502     
- Misses      14099    16106    +2007     
+ Partials     2160     1787     -373     

Flag	Coverage Δ
cluster	41.10% <17.65%> (-0.24%)	⬇️
dm	24.73% <17.65%> (-0.10%)	⬇️
playground	?
tiup	?
unittest	21.29% <0.00%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
pkg/cluster/ansible/inventory.go	57.78% <ø> (ø)
pkg/cluster/template/config/prometheus.go	78.35% <0.00%> (+4.56%)	⬆️
pkg/cluster/spec/monitoring.go	67.80% <18.75%> (-4.93%)	⬇️
main.go	0.00% <0.00%> (-100.00%)	⬇️
pkg/repository/utils/hash.go	0.00% <0.00%> (-81.25%)	⬇️
components/playground/monitor.go	0.00% <0.00%> (-81.05%)	⬇️
pkg/repository/model/publish.go	0.00% <0.00%> (-80.00%)	⬇️
components/playground/command.go	0.00% <0.00%> (-79.17%)	⬇️
pkg/cluster/template/config/ngmonitoring.go	0.00% <0.00%> (-76.47%)	⬇️
cmd/env.go	25.00% <0.00%> (-70.00%)	⬇️
... and 56 more

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[ti-chi-bot]

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[AstroProfundis]

What will happen if there is no ngm instance available in the cluster?

[AstroProfundis]

Suggested change

	// AddGrafana add an Grafana exporter address
	// AddGrafana add an Grafana address

[AstroProfundis]

/merge