cluster: fix Grafana error datasource not found

[srstack]

What problem does this PR solve?

close #1762

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]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• nexustar

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[codecov-commenter]

Codecov Report

Merging #1768 (8aa8acc) into master (9681e46) will decrease coverage by 0.83%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1768      +/-   ##
==========================================
- Coverage   53.09%   52.26%   -0.83%     
==========================================
  Files         303      303              
  Lines       34429    34436       +7     
==========================================
- Hits        18280    17997     -283     
- Misses      13994    14338     +344     
+ Partials     2155     2101      -54     

Flag	Coverage Δ
cluster	39.58% <100.00%> (-1.73%)	⬇️
dm	24.86% <100.00%> (+0.09%)	⬆️
playground	12.61% <100.00%> (-0.01%)	⬇️
tiup	14.40% <ø> (ø)
unittest	21.32% <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/manager/destroy.go	52.59% <ø> (ø)
components/playground/grafana.go	71.01% <100.00%> (-0.41%)	⬇️
pkg/cluster/manager/builder.go	72.74% <100.00%> (+0.85%)	⬆️
pkg/cluster/manager/scale_in.go	48.81% <100.00%> (+0.62%)	⬆️
pkg/cluster/template/config/alertmanager.go	0.00% <0.00%> (-55.00%)	⬇️
components/cluster/command/edit_config.go	47.06% <0.00%> (-35.29%)	⬇️
components/cluster/command/upgrade.go	46.15% <0.00%> (-30.77%)	⬇️
pkg/cluster/spec/tikv.go	34.75% <0.00%> (-27.87%)	⬇️
pkg/cluster/operation/upgrade.go	29.41% <0.00%> (-26.47%)	⬇️
pkg/utils/retry.go	46.43% <0.00%> (-16.07%)	⬇️
... and 9 more

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[AstroProfundis]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 8aa8acc