feat(module:auto-complete): close panel when the trigger element blur

[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?

[ ] Bugfix
[x] 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: #2885

What is the new behavior?

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[netlify]

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[codecov]

Codecov Report

Merging #2916 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #2916      +/-   ##
==========================================
+ Coverage   97.36%   97.36%   +<.01%     
==========================================
  Files         524      524              
  Lines       11040    11041       +1     
  Branches      782      782              
==========================================
+ Hits        10749    10750       +1     
  Misses        190      190              
  Partials      101      101

Impacted Files	Coverage Δ
...auto-complete/nz-autocomplete-trigger.directive.ts	99.3% <100%> (ø)	⬆️

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[vthinkxie]

LGTM