fix(module:page-header): fix page-header style break change

[vthinkxie]

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?

[ ] 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
[ ] No

Other information

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[codecov]

Codecov Report

Merging #3803 into master will increase coverage by 0.02%.
The diff coverage is 50%.

@@            Coverage Diff             @@
##           master    #3803      +/-   ##
==========================================
+ Coverage   95.35%   95.38%   +0.02%     
==========================================
  Files         706      706              
  Lines       14558    14558              
  Branches     1923     1923              
==========================================
+ Hits        13882    13886       +4     
+ Misses        246      244       -2     
+ Partials      430      428       -2

Impacted Files	Coverage Δ
components/page-header/nz-page-header-cells.ts	100% <ø> (ø)	⬆️
components/core/util/measure-scrollbar.ts	88% <50%> (+16%)	⬆️

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