perf(module:tree): change the collapsed of the treeNode to ngIf

[qqabcv520]

Change the collapsed of the treeNode from display: none to *ngIf.

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
[ ] Feature
[ ] Code style update (formatting, local variables)
[x] 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: #4182

Use display: none to collapse treeNode.

What is the new behavior?

Change the collapsed of the treeNode from display: none to *ngIf.

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[netlify]

Deploy preview for ng-zorro-master ready!

Built with commit de1b6e3

https://deploy-preview-3947--ng-zorro-master.netlify.com

[wenqi73]

测试有误，请修改一下。

[codecov]

Codecov Report

Merging #3947 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #3947      +/-   ##
==========================================
- Coverage   92.18%   92.17%   -0.01%     
==========================================
  Files         520      520              
  Lines       11011    11013       +2     
  Branches     1995     1995              
==========================================
+ Hits        10150    10151       +1     
- Misses        430      431       +1     
  Partials      431      431

Impacted Files	Coverage Δ
components/tree/nz-tree-node.component.ts	88.83% <ø> (ø)	⬆️
components/core/animation/collapse.ts	100% <100%> (ø)	⬆️
components/core/tree/nz-tree-base-node.ts	88.57% <0%> (-0.64%)	⬇️

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[qqabcv520]

测试有误，请修改一下。

因为实现折叠的方式变了，之前的测试代码要修改，之前 @simplejason 说修改一直没改

[simplejason]

run

git fetch upstream
git pull --rebase upstream master

when you have synced codes with master, check https://github.com/simplejason/ng-zorro-antd/commit/a63700d9f0da2741f1c15e304fa80b989a7ace4e to change your spec file.

[simplejason]

run

git fetch upstream
git pull --rebase upstream master

when you have synced codes with master, check https://github.com/simplejason/ng-zorro-antd/commit/a63700d9f0da2741f1c15e304fa80b989a7ace4e to change your spec file.

we will merge it after testing passed

[simplejason]

LGTM