fix(module:image): resolve memory 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

What is the current behavior?

Currently, event listeners are not removed from the image element when the directive is destroyed, tho they keep capturing this and prevent the directive from being GC'd.

__ngContext__[2] & 256 is lView[FLAGS] & LViewFlags.Destroyed, which checks if the directive is in destroyed status (it is):

The image preview can be closed by clicking on the close button on either container. This means that one of the streams will emit (containerClick or closeClick). If containerClick emits, then the closeClick will never complete and vice-versa:

What is the new behavior?

The NzImageDirective is GC'd successfully.

Does this PR introduce a breaking change?

[x] No

[zorro-bot]

This preview will be available after the AzureCI is passed.

[codecov]

Codecov Report

Merging #6856 (5689483) into master (f89cb38) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head 5689483 differs from pull request most recent head e8bd36e. Consider uploading reports for the commit e8bd36e to get more accurate results

@@           Coverage Diff           @@
##           master    #6856   +/-   ##
=======================================
  Coverage   89.52%   89.52%           
=======================================
  Files         489      489           
  Lines       15802    15806    +4     
  Branches     2572     2572           
=======================================
+ Hits        14146    14150    +4     
  Misses       1015     1015           
  Partials      641      641           

Impacted Files	Coverage Δ
components/image/image-preview-ref.ts	100.00% <100.00%> (ø)
components/image/image.directive.ts	90.66% <100.00%> (+0.25%)	⬆️
components/time-picker/time-holder.ts	94.73% <0.00%> (-1.06%)	⬇️
components/modal/modal-container.ts	92.89% <0.00%> (+0.54%)	⬆️

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