fix(module:popconfirm): reverting missing nzPopconfirmVisibleChange

[volvachev]

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?

Event nzPopconfirmVisibleChange missing from the component.

Issue Number: #7337

What is the new behavior?

Returns the deleted output event(nzPopconfirmVisibleChange) from the component.

Does this PR introduce a breaking change?

[ ] Yes
[x] No

[codecov]

Codecov Report

Merging #7338 (df0694c) into master (b517bd4) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head df0694c differs from pull request most recent head 0a55697. Consider uploading reports for the commit 0a55697 to get more accurate results

@@           Coverage Diff           @@
##           master    #7338   +/-   ##
=======================================
  Coverage   91.62%   91.62%           
=======================================
  Files         487      487           
  Lines       16013    16014    +1     
  Branches     2604     2604           
=======================================
+ Hits        14672    14673    +1     
  Misses       1027     1027           
  Partials      314      314           

Impacted Files	Coverage Δ
components/popconfirm/popconfirm.ts	98.70% <100.00%> (+0.01%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update b517bd4...0a55697. Read the comment docs.

[simplejason]

LGTM