fix(module:description): fix colspan calcuation in horizontal bordered

[wzhudev]

close #4013

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

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[codecov]

Codecov Report

Merging #4014 into master will increase coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #4014      +/-   ##
==========================================
+ Coverage   92.41%   92.45%   +0.03%     
==========================================
  Files         506      506              
  Lines       10749    10749              
  Branches     1942     1942              
==========================================
+ Hits         9934     9938       +4     
+ Misses        400      398       -2     
+ Partials      415      413       -2

Impacted Files	Coverage Δ
components/time-picker/time-holder.ts	96.49% <0%> (+0.87%)	⬆️
components/core/util/text-measure.ts	87.61% <0%> (+2.85%)	⬆️

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