fix(comp:form): the content of form-item is block

[danranVm]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines
• Tests for the changes have been added/updated or not needed
• Docs and demo have been added/updated or not needed

What is the current behavior?

回退 #1032 的代码，解决 form-item 内容居中的问题。

What is the new behavior?

Other information

[idux-bot]

This preview will be available after the AzureCI is passed.

[codecov]

Codecov Report

Merging #1088 (69c513d) into main (c6f3ea0) will not change coverage.
The diff coverage is n/a.

❗ Current head 69c513d differs from pull request most recent head e7c20a4. Consider uploading reports for the commit e7c20a4 to get more accurate results

@@           Coverage Diff           @@
##             main    #1088   +/-   ##
=======================================
  Coverage   96.92%   96.92%           
=======================================
  Files         317      317           
  Lines       30398    30398           
  Branches     2790     2790           
=======================================
  Hits        29463    29463           
  Misses        935      935           

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.