fix(showcase): fix the problem that the pop-up code is not displayed

[shuizhongxiong]

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-mobile/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
[x] Application (the showcase website) / infrastructure changes
[ ] Other... Please describe:

What is the current behavior?

官网 demo 代码弹窗不显示代码内容。

Issue Number: N/A

What is the new behavior?

弹窗显示代码内容。

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[codecov]

Codecov Report

Merging #814 (fc314e2) into master (7b72c02) will not change coverage.
The diff coverage is n/a.

❗ Current head fc314e2 differs from pull request most recent head 1edf9a0. Consider uploading reports for the commit 1edf9a0 to get more accurate results

@@           Coverage Diff           @@
##           master     #814   +/-   ##
=======================================
  Coverage   86.71%   86.71%           
=======================================
  Files         164      164           
  Lines        6614     6614           
  Branches     1107     1107           
=======================================
  Hits         5735     5735           
  Misses        429      429           
  Partials      450      450           

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