fix(module: code-editor): fix wrong initialization with diff mode

[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]

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[netlify]

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[wzhudev]

LGTM

[codecov]

Codecov Report

Merging #4532 into master will increase coverage by <.01%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master    #4532      +/-   ##
==========================================
+ Coverage   93.23%   93.23%   +<.01%     
==========================================
  Files         519      519              
  Lines       12822    12823       +1     
  Branches     2013     2013              
==========================================
+ Hits        11954    11955       +1     
- Misses        452      453       +1     
+ Partials      416      415       -1

Impacted Files	Coverage Δ
components/code-editor/nz-code-editor.component.ts	17.89% <0%> (-0.2%)	⬇️
components/time-picker/time-holder.ts	97.31% <0%> (+0.67%)	⬆️

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