cluster: print more clear warning when scale in with --force

[AstroProfundis]

What problem does this PR solve?

Close #1453

Related changes

• Need to cherry-pick to the release branch

Release notes:

NONE

[lucklove]

LGTM

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• lucklove

To complete the pull request process, please ask the reviewers in the list to review by filling /cc @reviewer in the comment.
After your PR has acquired the required number of LGTMs, you can assign this pull request to the committer in the list by filling /assign @committer in the comment to help you merge this pull request.

The full list of commands accepted by this bot can be found here.

Reviewer can indicate their review by submitting an approval review.
Reviewer can cancel approval by submitting a request changes review.

[AstroProfundis]

/merge

[ti-chi-bot]

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

Commit hash: 9f44afc

[codecov-commenter]

Codecov Report

Merging #1477 (89dedd5) into master (35998e0) will increase coverage by 6.28%.
The diff coverage is 33.33%.

❗ Current head 89dedd5 differs from pull request most recent head 4ff240f. Consider uploading reports for the commit 4ff240f to get more accurate results

@@            Coverage Diff             @@
##           master    #1477      +/-   ##
==========================================
+ Coverage   26.27%   32.56%   +6.28%     
==========================================
  Files         267      228      -39     
  Lines       23784    20745    -3039     
==========================================
+ Hits         6249     6755     +506     
+ Misses      16714    12961    -3753     
- Partials      821     1029     +208     

Flag	Coverage Δ
cluster	32.56% <33.33%> (?)
integrate	32.56% <33.33%> (+16.39%)	⬆️
tiup	?
unittest	?

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

Impacted Files	Coverage Δ
pkg/cluster/manager/scale_in.go	51.92% <33.33%> (+51.92%)	⬆️
pkg/utils/regexp.go	0.00% <0.00%> (-100.00%)	⬇️
pkg/repository/store/store.go	0.00% <0.00%> (-100.00%)	⬇️
pkg/telemetry/telemetry.go	0.00% <0.00%> (-83.34%)	⬇️
pkg/repository/utils/hash.go	0.00% <0.00%> (-83.34%)	⬇️
pkg/repository/model/publish.go	0.00% <0.00%> (-83.34%)	⬇️
pkg/utils/diff.go	0.00% <0.00%> (-83.15%)	⬇️
pkg/repository/store/local.go	0.00% <0.00%> (-82.61%)	⬇️
pkg/utils/semver.go	5.51% <0.00%> (-81.11%)	⬇️
pkg/meta/err.go	0.00% <0.00%> (-77.78%)	⬇️
... and 221 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 35998e0...4ff240f. Read the comment docs.