cluster: fix wrong keys detecting host arch

[AstroProfundis]

What problem does this PR solve?

Introduced in #1423

$ tiup cluster deploy aws-test-v530 v5.3.0 topo.yaml -i id_rsa -u centos
Starting component `cluster`: /home/centos/.tiup/components/cluster/v1.6.0/tiup-cluster deploy aws-test-v530 v5.3.0 topo.yaml -i id_rsa -u centos





+ Detect CPU Arch
  - Detecting node 172.31.38.22 ... ⠼ Shell: host=172.31.38.22, sudo=false, command=`uname -m`
  - Detecting node 172.31.40.219 ... ⠼ Shell: host=172.31.40.219, sudo=false, command=`uname -m`
+ Detect CPU Arch
+ Detect CPU Arch
  - Detecting node 172.31.38.22 ... Done
  - Detecting node 172.31.40.219 ... Done
  - Detecting node 172.31.46.81 ... Done
  - Detecting node 172.31.42.64 ... Done
  - Detecting node 172.31.37.178 ... Done
  - Detecting node 172.31.36.128 ... Done
  - Detecting node 172.31.34.177 ... Done
  - Detecting node 172.31.41.3 ... Done
  - Detecting node 172.31.36.51 ... Done

Error: no check results found for 172.31.47.49

Verbose debug logs has been written to /home/centos/.tiup/logs/tiup-cluster-debug-2021-11-04-09-09-08.log.
Error: run `/home/centos/.tiup/components/cluster/v1.6.0/tiup-cluster` (wd:/home/centos/.tiup/data/SnmiNyB) failed: exit status 1

While 172.31.47.79 is the console machine itself and has multiple instances defined on it in the topology.

What is changed and how it works?

When detecting host arch, empty value should not be added to the host set before checking of the value of its arch field.

Check List

Tests

• Manual test (add detailed scripts or steps below)

Related changes

• Need to cherry-pick to the release branch

Release notes:

NONE

[ti-chi-bot]

[REVIEW NOTIFICATION]

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• nexustar

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[AstroProfundis]

/merge

[ti-chi-bot]

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

Commit hash: 8fdff78

[codecov-commenter]

Codecov Report

Merging #1610 (11b51ef) into master (109ebff) will decrease coverage by 2.23%.
The diff coverage is n/a.

❗ Current head 11b51ef differs from pull request most recent head ba156bc. Consider uploading reports for the commit ba156bc to get more accurate results

@@            Coverage Diff             @@
##           master    #1610      +/-   ##
==========================================
- Coverage   15.71%   13.47%   -2.24%     
==========================================
  Files         149      154       +5     
  Lines       15097    15651     +554     
==========================================
- Hits         2372     2109     -263     
- Misses      12208    13140     +932     
+ Partials      517      402     -115     

Flag	Coverage Δ
integrate	13.47% <ø> (-2.24%)	⬇️
playground	13.47% <ø> (?)
tiup	?
unittest	?

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

Impacted Files	Coverage Δ
pkg/repository/store/store.go	0.00% <0.00%> (-100.00%)	⬇️
pkg/repository/utils/hash.go	0.00% <0.00%> (-83.34%)	⬇️
pkg/repository/model/publish.go	0.00% <0.00%> (-83.34%)	⬇️
pkg/repository/store/local.go	0.00% <0.00%> (-82.61%)	⬇️
pkg/telemetry/telemetry.go	0.00% <0.00%> (-66.67%)	⬇️
pkg/repository/v1manifest/keys.go	5.33% <0.00%> (-58.67%)	⬇️
pkg/repository/merge_mirror.go	0.00% <0.00%> (-58.51%)	⬇️
pkg/utils/args.go	0.00% <0.00%> (-50.00%)	⬇️
pkg/repository/store/txn.go	0.00% <0.00%> (-49.67%)	⬇️
pkg/repository/model/model.go	0.00% <0.00%> (-47.52%)	⬇️
... and 60 more

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