fix(module:cdk): resolve leak

[arturovt]

PR Checklist

• 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

[x] Bugfix

[zorro-bot]

This preview will be available after the AzureCI is passed.

[codecov]

Codecov Report

Merging #7139 (6f52021) into master (ab78821) will decrease coverage by 0.04%.
The diff coverage is 100.00%.

❗ Current head 6f52021 differs from pull request most recent head de79f7b. Consider uploading reports for the commit de79f7b to get more accurate results

@@            Coverage Diff             @@
##           master    #7139      +/-   ##
==========================================
- Coverage   89.75%   89.70%   -0.05%     
==========================================
  Files         488      488              
  Lines       15937    15945       +8     
  Branches     2579     2579              
==========================================
  Hits        14304    14304              
- Misses       1001     1007       +6     
- Partials      632      634       +2     

Impacted Files	Coverage Δ
components/anchor/anchor.component.ts	97.11% <ø> (ø)
components/collapse/collapse-panel.component.ts	93.10% <ø> (ø)
components/drawer/drawer.component.ts	98.01% <ø> (ø)
components/form/form-control.component.ts	93.44% <ø> (ø)
components/layout/sider.component.ts	94.82% <ø> (ø)
components/transfer/transfer-list.component.ts	96.22% <ø> (ø)
components/transfer/transfer-search.component.ts	100.00% <ø> (ø)
components/cascader/cascader-li.component.ts	100.00% <100.00%> (ø)
components/cascader/cascader.component.ts	94.79% <100.00%> (+0.03%)	⬆️
components/skeleton/skeleton-element.component.ts	95.00% <100.00%> (+0.26%)	⬆️
... and 13 more

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[hsuanxyz]

LGTM