fix(module:tree): word misspelling(destory -> destroy)

[YuhuiM]

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)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Application (the showcase website) / infrastructure changes
[x] Other... Please describe: word misspelling

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

[netlify]

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Built with commit d1ffd11

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[codecov]

Codecov Report

Merging #2914 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master    #2914   +/-   ##
=======================================
  Coverage   97.36%   97.36%           
=======================================
  Files         526      526           
  Lines       11041    11041           
  Branches      787      787           
=======================================
  Hits        10750    10750           
  Misses        190      190           
  Partials      101      101

Impacted Files	Coverage Δ
components/tree/nz-tree-node.component.ts	98.95% <100%> (ø)	⬆️

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[vthinkxie]

LGTM