cluster: fix port conflict check for tiflash instances

[AstroProfundis]

What problem does this PR solve?

The Flash* ports are not checked for conflicts for tiflash instances.

Check List

Tests

• Unit test

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• srstack

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[codecov-commenter]

Codecov Report

Merging #1805 (eeeac68) into master (62dc752) will decrease coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1805      +/-   ##
==========================================
- Coverage   53.05%   53.03%   -0.02%     
==========================================
  Files         303      303              
  Lines       34641    34644       +3     
==========================================
- Hits        18378    18373       -5     
- Misses      14102    14113      +11     
+ Partials     2161     2158       -3     

Flag	Coverage Δ
cluster	41.28% <100.00%> (-0.04%)	⬇️
dm	24.83% <0.00%> (-<0.01%)	⬇️
playground	12.63% <0.00%> (-<0.01%)	⬇️
tiup	14.42% <0.00%> (+0.02%)	⬆️
unittest	21.31% <100.00%> (+0.01%)	⬆️

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

Impacted Files	Coverage Δ
pkg/cluster/spec/validate.go	92.97% <100.00%> (+0.03%)	⬆️
pkg/utils/retry.go	46.43% <0.00%> (-16.07%)	⬇️
pkg/cluster/spec/tikv.go	61.31% <0.00%> (-1.31%)	⬇️
pkg/cluster/api/pdapi.go	56.94% <0.00%> (-0.53%)	⬇️
pkg/cluster/spec/tiflash.go	69.18% <0.00%> (+0.67%)	⬆️
pkg/repository/store/txn.go	59.04% <0.00%> (+2.13%)	⬆️

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[srstack]

/merge

[ti-chi-bot]

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

Commit hash: eeeac68