11.1.0+ec03c7fb09

[fix(module:grid): nzGutter support string type (#6450)

• fix(module:grid): nzGutter support string type

The following code style is better in strictTemplates mode:

<nz-row [nzGutter]="16">

better:

<nz-row nzGutter="16">

• docs: update

• chore: fix number check](NG-ZORRO/ng-zorro-antd@ec03c7fb09) ec03c7fb09
  github:NG-ZORRO/ng-zorro-antd-builds#79e2617a0523b0a2ac3813d9f43d5d68c38305bc