fix(module:modal): some cases there is no changes detected

[hsuanxyz]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/NG-ZORRO/ng-zorro-antd/blob/master/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Application (the showcase website) / infrastructure changes
[ ] Other... Please describe:

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[zorro-bot]

This preview will be available after the AzureCI is passed.

[codecov]

Codecov Report

Merging #5332 into master will increase coverage by 0.12%.
The diff coverage is 92.30%.

@@            Coverage Diff             @@
##           master    #5332      +/-   ##
==========================================
+ Coverage   91.10%   91.22%   +0.12%     
==========================================
  Files         453      453              
  Lines       13891    13895       +4     
  Branches     2126     2131       +5     
==========================================
+ Hits        12655    12676      +21     
+ Misses        737      722      -15     
+ Partials      499      497       -2     

Impacted Files	Coverage Δ
...ponents/modal/modal-confirm-container.component.ts	100.00% <ø> (ø)
components/modal/modal-container.component.ts	100.00% <ø> (ø)
components/modal/modal-container.ts	94.02% <90.32%> (+6.59%)	⬆️
components/modal/modal-ref.ts	97.82% <100.00%> (+0.02%)	⬆️
components/modal/modal.component.ts	96.80% <100.00%> (+0.06%)	⬆️
components/core/config/config.ts	100.00% <0.00%> (ø)
components/table/src/table/tr-measure.component.ts	100.00% <0.00%> (+13.04%)	⬆️
... and 1 more

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