feat: add [compositionFilter] to InputItem

[Eve-Sama]

close #732

PR Checklist

Please check if your PR fulfills the following requirements:

• [x] The commit message follows our guidelines: https://github.com/NG-ZORRO/ng-zorro-antd-mobile/blob/master/CONTRIBUTING.md#commit
• [x] Tests for the changes have been added (for bug fixes / features)
• [x] 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
[x] Documentation content changes
[ ] Application (the showcase website) / infrastructure changes
[ ] Other... Please describe:

What is the current behavior?

Issue Number: #731

What is the new behavior?

当[compositionFilter]为true时, 在移动端输入内容, 如中文等需要预览状态的语言, 在完成输入前是不会触发ngModelChange的, 也就是无法更改值. 当[compositionFilter]为false时, 即便在预览模式下也会修改值.

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[codecov[bot]]

Codecov Report

Merging #735 into master will increase coverage by 0.00%. The diff coverage is 50.00%.

@@           Coverage Diff           @@
##           master     #735   +/-   ##
=======================================
  Coverage   87.16%   87.16%           
=======================================
  Files         164      164           
  Lines        6747     6748    +1     
  Branches     1104     1104           
=======================================
+ Hits         5881     5882    +1     
  Misses        421      421           
  Partials      445      445           

Impacted Files	Coverage Δ
components/input-item/input-item.component.ts	93.59% <50.00%> (+0.03%)	:arrow_up:

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