cluster: support spec template for exec

[AstroProfundis]

What problem does this PR solve?

We had added a simple implementation of rendering input as template with instance specification in #1044 which makes it easier to close #894

What is changed and how it works?

Render command string as template before sending it to executor.

Check List

Tests

• Manual test (add detailed scripts or steps below)

Code changes

• Has exported function/method change
• Has exported variable/fields change

Side effects

• Increased code complexity

Release notes:

NONE

[codecov-io]

Codecov Report

Merging #1048 (9956588) into master (9caaca7) will decrease coverage by 9.45%.
The diff coverage is 59.18%.

@@            Coverage Diff             @@
##           master    #1048      +/-   ##
==========================================
- Coverage   55.94%   46.48%   -9.46%     
==========================================
  Files         282      281       -1     
  Lines       19869    19858      -11     
==========================================
- Hits        11115     9231    -1884     
- Misses       7031     9155    +2124     
+ Partials     1723     1472     -251     

Flag	Coverage Δ
cluster	35.17% <59.18%> (-8.84%)	⬇️
dm	?
integrate	41.27% <59.18%> (-8.98%)	⬇️
playground	20.30% <ø> (ø)
tiup	16.47% <ø> (-0.03%)	⬇️
unittest	22.25% <0.00%> (-0.04%)	⬇️

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

Impacted Files	Coverage Δ
components/cluster/command/check.go	6.60% <0.00%> (-72.89%)	⬇️
pkg/cluster/manager/transfer.go	18.66% <0.00%> (-37.34%)	⬇️
pkg/cluster/manager/exec.go	64.00% <64.28%> (-15.49%)	⬇️
pkg/cluster/task/builder.go	80.81% <100.00%> (-19.19%)	⬇️
pkg/cluster/task/shell.go	64.28% <100.00%> (+9.74%)	⬆️
pkg/cluster/task/task.go	73.21% <100.00%> (-8.93%)	⬇️
components/dm/main.go	0.00% <0.00%> (-100.00%)	⬇️
components/dm/spec/bindversion.go	0.00% <0.00%> (-100.00%)	⬇️
components/dm/spec/cluster.go	0.00% <0.00%> (-87.50%)	⬇️
components/dm/spec/logic.go	0.60% <0.00%> (-78.66%)	⬇️
... and 94 more

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[lucklove]

Rest LGTM

[lucklove]

/lgtm

[lucklove]

/merge

[ti-chi-bot]

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

Commit hash: 006b9a4

[ti-chi-bot]

@AstroProfundis: Your PR has out-of-dated, I have automatically updated it for you.

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