feat: PageHeader support classname

[chenshuai2144]

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This is a ...

• New feature
• Bug fix
• Site / document update
• Component style update
• TypeScript definition update
• Refactoring
• Code style optimization
• Branch merge
• Other (about what?)

What's the background?

#15157

API Realization (Optional if not new feature)

1. Basic thought of solution and other optional proposal.
2. List final API realization and usage sample.
3. GIF or snapshot should be provided if includes UI/interactive modification.

What's the effect? (Optional if not new feature)

1. Does this PR affect user? Which part will be affected?
2. What will say in changelog?
3. Does this PR contains potential break change or other risk?

Changelog description (Optional if not new feature)

 1. English description
    PageHeader support `classname` prop.
 2. Chinese description (optional)
    PageHeader 支持 `className` prop。

Self Check before Merge

• Doc is updated/provided or not needed
• Demo is updated/provided or not needed
• TypeScript definition is updated/provided or not needed
• Changelog is provided or not needed

Additional Plan? (Optional if not new feature)

If this PR related with other PR or following info. You can type here.

[codecov]

Codecov Report

Merging #15159 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master   #15159   +/-   ##
=======================================
  Coverage   93.32%   93.32%           
=======================================
  Files         249      249           
  Lines        6671     6671           
  Branches     1925     1945   +20     
=======================================
  Hits         6226     6226           
+ Misses        444      442    -2     
- Partials        1        3    +2

Impacted Files	Coverage Δ
components/page-header/index.tsx	100% <100%> (ø)	⬆️
components/time-picker/index.tsx	81.94% <0%> (ø)	⬆️
components/transfer/index.tsx	85.43% <0%> (ø)	⬆️

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