fix(module:auto-complete): dropdown position error with group-input

[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]

This preview will be available after the AzureCI is passed.

[codecov]

Codecov Report

Merging #5157 into master will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #5157      +/-   ##
==========================================
+ Coverage   91.41%   91.45%   +0.03%     
==========================================
  Files         547      547              
  Lines       13790    13793       +3     
  Branches     2148     2149       +1     
==========================================
+ Hits        12606    12614       +8     
+ Misses        713      708       -5     
  Partials      471      471              

Impacted Files	Coverage Δ
components/auto-complete/autocomplete.module.ts	100.00% <ø> (ø)
components/input/input.module.ts	100.00% <ø> (ø)
...ts/auto-complete/autocomplete-trigger.directive.ts	95.78% <100.00%> (+0.02%)	⬆️
components/input/input-group.component.ts	100.00% <100.00%> (ø)
components/table/src/table/tr-measure.component.ts	100.00% <0.00%> (+13.04%)	⬆️
components/table/src/table/tbody.component.ts	100.00% <0.00%> (+14.28%)	⬆️

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[vthinkxie]

lgtm