fix(module:button): fix button loading bug

[vthinkxie]

close #2191

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

[codecov]

Codecov Report

Merging #2251 into master will decrease coverage by 0.08%.
The diff coverage is 76.74%.

@@            Coverage Diff             @@
##           master    #2251      +/-   ##
==========================================
- Coverage   95.87%   95.78%   -0.09%     
==========================================
  Files         485      485              
  Lines       12136    12145       +9     
  Branches     1625     1628       +3     
==========================================
- Hits        11635    11633       -2     
- Misses        145      152       +7     
- Partials      356      360       +4

Impacted Files	Coverage Δ
components/core/util/check.ts	83.33% <70%> (-7.3%)	⬇️
components/button/nz-button.component.ts	93.81% <82.6%> (-6.19%)	⬇️
components/table/nz-table.component.ts	93.88% <0%> (-1.12%)	⬇️
components/tabs/nz-tabset.component.ts	96.58% <0%> (+0.85%)	⬆️

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