feat(module:tooltip): add nzTooltipColor

[wzhudev]

close #5884

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
[ ] Other... Please describe:

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Does this PR introduce a breaking change?

[ ] Yes
[ ] No

Other information

[codecov]

Codecov Report

Merging #5896 into master will decrease coverage by 0.02%.
The diff coverage is 94.73%.

@@            Coverage Diff             @@
##           master    #5896      +/-   ##
==========================================
- Coverage   90.00%   89.98%   -0.03%     
==========================================
  Files         463      464       +1     
  Lines       13986    13998      +12     
  Branches     2297     2299       +2     
==========================================
+ Hits        12588    12596       +8     
- Misses        854      857       +3     
- Partials      544      545       +1     

Impacted Files	Coverage Δ
components/tooltip/base.ts	91.00% <80.00%> (-0.96%)	⬇️
components/core/color/color.ts	100.00% <100.00%> (ø)
components/tag/tag.component.ts	100.00% <100.00%> (ø)
components/tooltip/tooltip.ts	100.00% <100.00%> (ø)
components/tabs/tab-nav-bar.component.ts	81.62% <0.00%> (-0.71%)	⬇️

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[hsuanxyz]

@wendellhu95 rebase

[wzhudev]

@wendellhu95 rebase

Will do, sir. 💯

[hsuanxyz]

LGTM