feat(module:modal): support set nzOkDisabled and nzCancelDisabled

[kekehaoz]

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
[x] 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?

Modal doesn't support set nzOkDisabled and nzCancelDisabled

Issue Number: #1838

What is the new behavior?

Modal support set nzOkDisabled and nzCancelDisabled

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[netlify]

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Built with commit b17add6

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[codecov]

Codecov Report

Merging #2856 into master will decrease coverage by 0.02%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #2856      +/-   ##
==========================================
- Coverage    95.5%   95.48%   -0.03%     
==========================================
  Files         523      523              
  Lines       12236    12241       +5     
  Branches     1668     1668              
==========================================
+ Hits        11686    11688       +2     
- Misses        197      198       +1     
- Partials      353      355       +2

Impacted Files	Coverage Δ
components/modal/nz-modal.component.ts	95.88% <100%> (+0.03%)	⬆️
components/radio/nz-radio-group.component.ts	90% <0%> (-3.34%)	⬇️
components/select/nz-option-container.component.ts	95.12% <0%> (-2.44%)	⬇️
components/anchor/nz-anchor.component.ts	100% <0%> (ø)	⬆️
components/radio/nz-radio.component.ts	98.3% <0%> (+0.02%)	⬆️

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[netlify]

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Built with commit e55bc65

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[wzhudev]

Should have a test.

[kekehaoz]

unit test already added